Windows version of Janus WebRTC Gateway

This release adds Windows 10 support to Janus WebRTC Gateway (awesome software from Meetecho). The package is cross-platform and can be compiled on Linux/OS X/Windows. The plan is to upstream the changes as soon as possible. The code was not thoroughly tested in very complex scenerios because it was good faith off-time effort. However, it works fine for large number of simultaneous audio and video connections and is pretty robust. To make this package more streamline all dependency packages were compiled on Windows 10 and its build scripts were released to https://github.com/Alexpux/MINGW-packages as well.

Attached installers contains binary versions of Janus WebRTC Gateway, header files and toolchains used for compilation. Packages can be used to develop custom plugins.