No longer rely on hashbangs for url routing

[psaiz]

Describe the feature:

Kibana keeps in the url all the attributes needed to display a page. Most of those attributes are kept in the anchor (after the '#').
The issue that I have is when I setup apache with shibboleth to do the authentication. Since the anchor is kept on the client side, and it is not passed to the web server, after a successful authentication, the page loses the anchor, and it gets redirected to the default page.

It would be nice if the attributes were not kept in the anchor. That way, they will stay after a successful authentication

Steps to reproduce:

1. Install kibana
2. Configure kibana behind an apache reverse proxy with shibboleth
3. Go to page https://myhost/app/kibana#/visualize/step/1?_g=(refreshInterval:(display:Off,pause:!f,value:0),time:(from:now-24h,mode:quick,to:now))
   (or any page with '#')

Errors in browser console (if relevant):

After a successful authentication, the page gets redirected to
https://myhost/app/kibana
(losing the anchor)

[epixa]

++ We should move to using the html5 URL history API instead of the current hashbang approach. This will help with things like proper logging as well.

The change is pretty drastic though, and it may be easiest to do once the new platform and new build tool are finished.

We have a bunch of issues that touch on this idea, but none that outright propose it as a standalone change.

[epixa]

No clue how I missed this when I originally commented, but this is a duplicate of #6219