Merge https://github.com/blmorris/micropython into Myriad2

py/builtin.c

py/builtin.h

py/emitinlinethumb.c

py/formatfloat.c

py/modsys.c

py/objarray.c

py/pfenv.h

py/pfenv_printf.c

py/py.mk

py/qstrdefs.h

py/stream.c

stmhal/file.c

stmhal/file.h

stmhal/main.c

stmhal/modos.c

stmhal/modpyb.c

stmhal/modtime.c

stmhal/mpconfigport.h

stmhal/portmodules.h

stmhal/printf.c