Emulator

I do have a word of warning. This will exhibit "choppy" behavior where the emulation crawls to a near-halt when compiling shaders, but it should cache the compiled shader bytecode forever after that, or at least until the LINEAR_DISKCACHE_VER value changes :). Then again, I didn't introduce any new functionality, just brought back old working functionality which a bug overtook and produced less of a slowdown for compiling shaders because it didn't append to the appropriate shader cache file and flush to disk.