Fix Fastmem in JitIL for massive speed gains.

JitIL's fastmem was stubbed out when Sonicadvance1 merged JitARMIL
into the tree. Since JitARMIL has been deleted, I simply re-arrange
the inheritance to base JitIL on Jitx86Base, so it can inherit the
backpatch function.

Povray Benchmark: 1985 seconds to 1316 seconds.
Merge pull request #1075 from phire/jitil-fastmem

Fix Fastmem in JitIL for massive speed gains.
JIT: fix JIT with conditional continue off, again
Merge pull request #1082 from FioraAeterna/fixccagain

JIT: fix JIT with conditional continue off, again
x64Emitter: add LZCNT/TZCNT support and detection

Also add a unit test.
JIT: use LZCNT in cntlzw
Merge pull request #1083 from FioraAeterna/lzcnt

Add LZCNT support, use in cntlzw