#510 Use Apache Felix maven-bundle-plugin to add osgi metadata.

[danfickle]

Should fix #510

For now, we export all packages, for simplicity. We could perhaps in the future make this more refined.

It generates something like this (for openhtmltopdf-core):

Manifest-Version: 1.0
Bnd-LastModified: 1595417324363
Build-Jdk-Spec: 1.8
Bundle-Description: Open HTML to PDF is a CSS 2.1 renderer written in Ja
 va.  This artifact contains the core rendering and layout code.
Bundle-License: http://www.gnu.org/licenses/lgpl.html
Bundle-ManifestVersion: 2
Bundle-Name: Openhtmltopdf Core Renderer
Bundle-SymbolicName: com.openhtmltopdf.core
Bundle-Version: 1.0.4.SNAPSHOT
Created-By: Apache Maven Bundle Plugin
Export-Package: com.openhtmltopdf.bidi;uses:="com.openhtmltopdf.css.cons
 tants,com.openhtmltopdf.layout,org.w3c.dom";version="1.0.4",com.openhtm
 ltopdf.context;uses:="com.openhtmltopdf.css.extend,com.openhtmltopdf.cs
 s.newmatch,com.openhtmltopdf.css.parser,com.openhtmltopdf.css.sheet,com
 .openhtmltopdf.css.style,com.openhtmltopdf.extend,com.openhtmltopdf.lay
 out,org.w3c.dom";version="1.0.4",com.openhtmltopdf.css.constants;uses:=
 "com.openhtmltopdf.css.parser,com.openhtmltopdf.css.parser.property,com
 .openhtmltopdf.css.style";version="1.0.4",com.openhtmltopdf.css.extend;
 uses:="com.openhtmltopdf.css.parser,com.openhtmltopdf.css.sheet,com.ope
 nhtmltopdf.layout,com.openhtmltopdf.render";version="1.0.4",com.openhtm
 ltopdf.css.extend.lib;uses:="com.openhtmltopdf.css.extend";version="1.0
 .4",com.openhtmltopdf.css.newmatch;uses:="com.openhtmltopdf.css.constan
 ts,com.openhtmltopdf.css.extend,com.openhtmltopdf.css.sheet";version="1
 .0.4",com.openhtmltopdf.css.parser;uses:="com.openhtmltopdf.css.constan
 ts,com.openhtmltopdf.css.sheet,org.w3c.dom";version="1.0.4",com.openhtm
 ltopdf.css.parser.property;uses:="com.openhtmltopdf.css.constants,com.o
 penhtmltopdf.css.parser,com.openhtmltopdf.css.sheet";version="1.0.4",co
 m.openhtmltopdf.css.sheet;uses:="com.openhtmltopdf.css.constants,com.op
 enhtmltopdf.css.newmatch,com.openhtmltopdf.css.parser,com.openhtmltopdf
 .css.style";version="1.0.4",com.openhtmltopdf.css.style;uses:="com.open
 htmltopdf.context,com.openhtmltopdf.css.constants,com.openhtmltopdf.css
 .newmatch,com.openhtmltopdf.css.parser,com.openhtmltopdf.css.style.deri
 ved,com.openhtmltopdf.css.value,com.openhtmltopdf.extend,com.openhtmlto
 pdf.render";version="1.0.4",com.openhtmltopdf.css.style.derived;uses:="
 com.openhtmltopdf.css.constants,com.openhtmltopdf.css.parser,com.openht
 mltopdf.css.style,com.openhtmltopdf.newtable";version="1.0.4",com.openh
 tmltopdf.css.value;uses:="com.openhtmltopdf.css.constants";version="1.0
 .4",com.openhtmltopdf.event;version="1.0.4",com.openhtmltopdf.extend;us
 es:="com.openhtmltopdf.css.extend,com.openhtmltopdf.css.parser,com.open
 htmltopdf.css.sheet,com.openhtmltopdf.css.style,com.openhtmltopdf.css.s
 tyle.derived,com.openhtmltopdf.css.value,com.openhtmltopdf.layout,com.o
 penhtmltopdf.render,com.openhtmltopdf.resource,org.w3c.dom";version="1.
 0.4",com.openhtmltopdf.extend.impl;uses:="com.openhtmltopdf.extend";ver
 sion="1.0.4",com.openhtmltopdf.layout;uses:="com.openhtmltopdf.bidi,com
 .openhtmltopdf.context,com.openhtmltopdf.css.constants,com.openhtmltopd
 f.css.extend,com.openhtmltopdf.css.newmatch,com.openhtmltopdf.css.parse
 r,com.openhtmltopdf.css.style,com.openhtmltopdf.css.value,com.openhtmlt
 opdf.extend,com.openhtmltopdf.newtable,com.openhtmltopdf.render,org.w3c
 .dom";version="1.0.4",com.openhtmltopdf.newtable;uses:="com.openhtmltop
 df.css.constants,com.openhtmltopdf.css.parser,com.openhtmltopdf.css.sty
 le,com.openhtmltopdf.css.style.derived,com.openhtmltopdf.layout,com.ope
 nhtmltopdf.render,org.w3c.dom";version="1.0.4",com.openhtmltopdf.output
 device.helper;uses:="com.openhtmltopdf.bidi,com.openhtmltopdf.css.const
 ants,com.openhtmltopdf.extend,com.openhtmltopdf.layout,com.openhtmltopd
 f.util,org.w3c.dom";version="1.0.4",com.openhtmltopdf.render;uses:="com
 .openhtmltopdf.bidi,com.openhtmltopdf.context,com.openhtmltopdf.css.con
 stants,com.openhtmltopdf.css.extend,com.openhtmltopdf.css.newmatch,com.
 openhtmltopdf.css.parser,com.openhtmltopdf.css.style,com.openhtmltopdf.
 css.style.derived,com.openhtmltopdf.css.value,com.openhtmltopdf.extend,
 com.openhtmltopdf.layout,org.w3c.dom";version="1.0.4",com.openhtmltopdf
 .render.displaylist;uses:="com.openhtmltopdf.css.style,com.openhtmltopd
 f.layout,com.openhtmltopdf.newtable,com.openhtmltopdf.render";version="
 1.0.4",com.openhtmltopdf.render.simplepainter;uses:="com.openhtmltopdf.
 layout,com.openhtmltopdf.newtable,com.openhtmltopdf.render";version="1.
 0.4",com.openhtmltopdf.resource;uses:="com.openhtmltopdf.extend,javax.x
 ml.transform,org.w3c.dom,org.xml.sax";version="1.0.4",com.openhtmltopdf
 .simple;uses:="com.openhtmltopdf.css.extend,com.openhtmltopdf.css.sheet
 ,com.openhtmltopdf.extend,org.w3c.dom";version="1.0.4",com.openhtmltopd
 f.simple.extend;uses:="com.openhtmltopdf.css.extend,com.openhtmltopdf.c
 ss.sheet,com.openhtmltopdf.extend,com.openhtmltopdf.layout,com.openhtml
 topdf.render,com.openhtmltopdf.simple,com.openhtmltopdf.simple.extend.f
 orm,javax.swing,org.w3c.dom";version="1.0.4",com.openhtmltopdf.simple.e
 xtend.form;uses:="com.openhtmltopdf.css.constants,com.openhtmltopdf.css
 .style,com.openhtmltopdf.extend,com.openhtmltopdf.layout,com.openhtmlto
 pdf.render,com.openhtmltopdf.simple.extend,javax.swing,org.w3c.dom";ver
 sion="1.0.4",com.openhtmltopdf.simple.xhtml;uses:="org.w3c.dom";version
 ="1.0.4",com.openhtmltopdf.simple.xhtml.controls;uses:="com.openhtmltop
 df.simple.xhtml,org.w3c.dom";version="1.0.4",com.openhtmltopdf.swing;us
 es:="com.openhtmltopdf.context,com.openhtmltopdf.css.constants,com.open
 htmltopdf.css.value,com.openhtmltopdf.event,com.openhtmltopdf.extend,co
 m.openhtmltopdf.layout,com.openhtmltopdf.render,com.openhtmltopdf.resou
 rce,com.openhtmltopdf.simple.extend,javax.swing,org.w3c.dom";version="1
 .0.4",com.openhtmltopdf.util;uses:="com.openhtmltopdf.layout";version="
 1.0.4",resources.conf;version="1.0.4",resources.css;version="1.0.4",res
 ources.schema.docbook;version="1.0.4",resources.schema.docbook.ent;vers
 ion="1.0.4",resources.schema.openhtmltopdf;version="1.0.4",resources.sc
 hema.xhtml;version="1.0.4",resources.schema.xhtml.element;version="1.0.
 4",resources.schema.xhtml.entity;version="1.0.4",resources.schema.xhtml
 .notation;version="1.0.4",resources.schema.xhtml.xhtml-1;version="1.0.4
 "
Import-Package: com.openhtmltopdf.bidi,com.openhtmltopdf.context,com.ope
 nhtmltopdf.css.constants,com.openhtmltopdf.css.extend,com.openhtmltopdf
 .css.extend.lib,com.openhtmltopdf.css.newmatch,com.openhtmltopdf.css.pa
 rser,com.openhtmltopdf.css.parser.property,com.openhtmltopdf.css.sheet,
 com.openhtmltopdf.css.style,com.openhtmltopdf.css.style.derived,com.ope
 nhtmltopdf.css.value,com.openhtmltopdf.event,com.openhtmltopdf.extend,c
 om.openhtmltopdf.layout,com.openhtmltopdf.newtable,com.openhtmltopdf.re
 nder,com.openhtmltopdf.render.displaylist,com.openhtmltopdf.render.simp
 lepainter,com.openhtmltopdf.resource,com.openhtmltopdf.simple,com.openh
 tmltopdf.simple.extend,com.openhtmltopdf.simple.extend.form,com.openhtm
 ltopdf.simple.xhtml,com.openhtmltopdf.simple.xhtml.controls,com.openhtm
 ltopdf.swing,com.openhtmltopdf.util,javax.imageio,javax.swing,javax.swi
 ng.border,javax.swing.event,javax.swing.plaf,javax.swing.plaf.basic,jav
 ax.swing.table,javax.swing.text,javax.swing.tree,javax.xml.parsers,java
 x.xml.transform,javax.xml.transform.dom,javax.xml.transform.sax,org.w3c
 .dom,org.xml.sax,org.xml.sax.helpers
Require-Capability: osgi.ee;filter:="(&(osgi.ee=JavaSE)(version=1.8))"
Tool: Bnd-5.1.1.202006162103

@zspitzer - you might like to take a look before I merge.