MStream v0.12: A Selfhost Music Streaming Server

I made a mistake, it should be v0.11 in the title. Some of the notable changes in this versions:

* MilkDrop Visualizer added to Webapp

* Better gapless playback in Webapp

* Server runs on OS, Windows, Linux, and even Android (through Termux)

* Reduced install time of binary releases

* Bug cleanup. Removed as many tickets as possible from the issues list