Separate out mpy core and unix version.

py/.gitignore

py/Makefile

py/asmthumb.c

py/compile.c

py/emitbc.c

py/emitcommon.c

py/emitcpy.c

py/emitinlinethumb.c

py/emitnative.c

py/emitpass1.c

py/emitthumb.c

py/parse.c

py/runtime.c

py/scope.c

py/vm.c

unix/Makefile

unix/main.c

unix/mpyconfig.h