Broke up CG_Init to enable JS event loop to breathe
Updated build / sound subsystems to decode audio with the web audio API, fixed issue with cgame not processing final load task, disabled playing of looping sounds when sound is missing, default rendering system to fast light path
Disabled GLSL_ValidateProgram, default r_picmip 0 for emscripten builds
async-ified FS_Startup, removed lazy-loaded sync i/o
Added JS platform to build