- Fixed LLVM style CL args for D2. - Moved main() into its own file gen/main.cpp - Fixed basic cross compilation - removed the option for setting OS - added support for llc's mattr, mcpu and mtriple switches - added basic ABI abstraction for return value rewrites, it's not perfect and will probably be completely rewritten once I get to handling parameter rewrites as well. - x86-64 extern(C) abi for cfloat returns now match (llvm-)gcc.

[Environment]
DFLAGS=-I@RUNTIME_DIR@ -I@RUNTIME_DIR@/lib/common -L-L%@P%/../lib -d-version=Tango -defaultlib=@RUNTIME_AIO@ -debuglib=@RUNTIME_AIO@