GTE Test

This is a GTE test program which will check the behavior of GTE registers and (official) GTE functions including unofficial usage of SF and LM, and in the case of the MVMVA funcion, CV, V and MX opcode bits. The opcodes are verified by comparing the results with a software simulation. Running the full test does take hours on a real PSX, and probably isn't much faster on an emulator either. However, the tests will give up after a certain amount of errors, so when run on an inaccurate emulator, it will complete more quickly.