Merge pull request #122 from parasyte/next

MIPS: Add HI, LO, and PC registers to MipsMapping.c
x86: prefix REP/REPNE are only relevant for MOVS/CMPS/SCAS/LDOS/STOS/INS/OUTS instructions
x86: correct instructions related to REP prefix
x86: handle REP MOVSD/CMPSD/SCASD/LODSD/STOSD properly (due to confused 128bit media instructions having the same mnemonics)
x86: detail operands for 'fstpnce st(0), st(0)' & 'fstpst(7), st(0)'
x86: add CL operand into details for 'SHL *, CL' instruction
x86: eliminate irrelevant prefixes in x86.prefix[] - such as f2/f3 prefixed irrelevant instructions
x86: cleanup unused code
python: test_x86.py print prefixes with a space between consecutive bytes