WIP PSX emulator in Go

TODO:

• timers
• controllers and maybe memcards?
• more interrupts like dma interrupts
• more gpu stuff like dithering and texture masking
• line rendering commands
• gpu command mirrors
• make a new struct GraphicsContext to handle all rendering stuff
• make hello.exe and hello2.exe work (fix double buffering and vsync issues)
• more cdrom commands
• gte
• icache, dcache, and texture cache
• pass amidog's psx_cpu test
• using this as reference, implement bus waitstates
• threaded software renderer
• implement scanline-based triangle rasterizer?
• add more stuff to cdrom to boot crash bandicoot
• web server for debugging
• wasm port
• savestates