zig: new port at version 0.5.0

See https://ziglang.org

lang/zig/Portfile

@@ -0,0 +1,36 @@
+# -*- coding: utf-8; mode: tcl; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- vim:fenc=utf-8:ft=tcl:et:sw=4:ts=4:sts=4
+
+PortSystem          1.0
+PortGroup           cmake 1.1
+PortGroup           compiler_blacklist_versions 1.0
+PortGroup           github 1.0
+
+github.setup        ziglang zig 0.5.0
+github.tarball_from archive
+revision            0
+
+categories          lang
+platforms           darwin
+license             MIT
+maintainers         {@felix userspace.com.au:felix} openmaintainer
+
+description         Zig programming language
+
+long_description    Zig is a general-purpose programming language designed for \
+                    robustness, optimality, and maintainability.
+
+homepage            https://ziglang.org/
+
+depends_lib-append  port:llvm-9.0
+
+checksums           rmd160  f6c957f66ebf9c981fea61cba4875081661ec3c6 \
+                    sha256  abe3e8ef064225f342bb24165e3c8a35f8f2c45930489a53897e835e984117eb \
+                    size    15743912
+
+set llvm_version    9.0
+set llvm_config     LLVM_CONFIG=llvm-config-mp-${llvm_version}
+
+compiler.blacklist-append *gcc* clang 
+compiler.fallback   macports-clang-${llvm_version}
+compiler.whitelist  macports-clang-${llvm_version}
+cmake.module_path   [list ${prefix}/libexec/llvm-${llvm_version}]