Further attempts at continuing jit blocks (disabled)

Scaffolding:
 * The armjit not detects free space when compiling (in case of long blocks), could fix things actually.
 * Invalid jumps are now skipped, instead of causing crashes (hit these while predicting in some games...)
 * Matches GetImm/etc. func names in x86jit.

I tried out the branch prediction approach.  It didn't really give great results.  I got a few extra percent in one game, and only by predicting forwards.  Most games are the same with it, and are worse if I predict backwards.

Only tried it on x86.  It might go a lot better on arm, not really sure.  If someone wants to try it, it's mostly a matter of copying the relevant sections from the x86 code, the regcache state should be roughly the same too.

I did copy over the loop unrolling to arm, and also tried function inlining (jump continuing) on both.  I didn't test heavily but didn't really see much benefit from it either.  It may be that it just needs to be optimized or only follow certain branches/jumps.  It does at least bring imm values all the way to syscalls often.

-[Unknown]