Changed switch/case orders - added syscall and break

new branch

-added syscall & break
-changed order of switch/case for more likely to use functions (mfhi is in here, but you will use 'add' more than you would mfhi)
-soft of reverted the mips_r arg order to what it was - i tested it and it looks to be working

let me know if i should keep anything instead of revert - or if i should change something here