DynASM/x86: Add lock prefix.
Add support for multilib distro builds.
Fix compilation on NetBSD/x64.

Thanks to Justin Cormack.
DynASM/x64: Add VREG support to mov64.

Thanks to Peter Cawley.
FFI: Properly unload loaded DLLs.
ARM: Fix register allocation when rematerializing FPRs.
Compatibility fix for old GCC versions.
Fix jit.flush(func|true).
Fix argument checks for math.deg()/math.rad().
Fix compiler warning.
Fix frame traversal for backtraces.
Recent GCC versions need more memory.
Fix quoting in xedkbuild.bat.
FFI: Fix argument checks for ffi.string().
FFI/x64: Fix passing of vector arguments to calls.
DynASM: Emit #line <n> <file> instead of #<n> <file>.
Fix snapshot restore for exit to function header.
Fix ABC elimination.
Check for MAP_32BIT presence instead of checking for Linux.
FFI: Rehash finalizer table after GC cycle, if needed.