OP-Decoder - Semi Final

I still have issue with RTS, but I handled all other.
And Terry, if you read this message, please check your module; It seems
like you already have OC_NO_SIZE mask, which should be used for LEA,
BEQ, and JSR, but your code is returning OC_LONG_SIZE mask.
If you fix this problem and handle RTS issue, we will have fully working
OP-decoder.