Fixed CMakeLists install target on Linux.
Replace lzma with xz. Tweaks to fix debug builds.
Turn pack200 into an actual library
``Working'' forge unpackers. Needs a lot of hardening but good for alpha.
Add tweaks to make things build on windows
Implemented xz and pack200 unpackers required for proper forge installation.

Merge branch 'feature_forge_unpackers' into develop

Conflicts:
	CMakeLists.txt
Add missing include
Merge branch 'master' into develop

This pulls in some changes I made to the CMakeLists file earlier.
Add run script to install.

Also renamed "translations_target" to "translations". The old name was
dumb and annoying.
Made run script instal as executable.

Also fixed a small bug with the run script.
Fixed an issue with the run script on Debian.
Set run script to load libs from bin folder.

I'd really like to put them in a separate "lib" folder, but CMake
doesn't want to.
Added a make target that prints the version name.
Add user agent header to most MultiMC download requests.