HashLink Nightly Build

[ci] Fix haxe hlc test suite errors (#908)

* [make] Fix install name for hdlls

This is required so that hlc programs can load the hdlls from rpath. It
also matches the behaviour of the cmake build, which sets these
automatically.

* [ci] Fix hlc tests failing due to missing haxelib

* [ci] Fix missing includes for hlc tests

* [ci] Set up msbuild for hlc tests

* [ci] Add shebang to dummy hl script

* [ci] Fix PATH entry for windows test suite

This was wrong before, which meant that the hl binary was not found and
the test suite recompiled from source.

* [ci] Add missing mbedtls install for mac test

* [ci] Make 32 bit mingw available in PATH

* [ci] Install 32 bit packages for linux tests

* [ci] Set msbuild platform for 32bit hlc tests

* [make] Remove hl.lib from vs2019 package

.lib files are only really useful for dlls and hdlls. When hl.lib is
included, compilers can get confused between libhl.lib and hl.lib which
results in hlc tests failing.

* Separate preprocessor flags in makefile template

This allows for overriding CFLAGS on the command line

* [tools] Add support for 32 bit hlc builds

In future this can be generalised for other architectures

* [ci] Pass 32 bit flag to hashlink build tool

This way we don't need to hack it with a cc wrapper.