Revamp qstrs: they now include length and hash.

Can now have null bytes in strings.  Can define ROM qstrs per port using
qstrdefsport.h
Merge branch 'master' of github.com:micropython/micropython

Conflicts:
	py/objstr.c
	py/py.mk
	py/stream.c
	unix/main.c
	unix/socket.c
Add len() support for arrays.
array: Implement iterator.
Add bytearray basic tests.
Merge pull request #202 from iabdalkader/master

Remove hardcoded PLL_M value
stm: Put TARGET in mpconfigport.h; support PYBv4.
stm: Put HSE_VALUE and other defines in mpconfigport.h.

mpconfigport.h is now included by stm32f4xx.h so that all STM files have
access to these defines.
stm: Clean up main.c; disable libgcc by default.

f2d and d2f functions from libgcc does not work correctly, most likely
due to the ABI being incorrect.  libgcc disabled for now.
Fix malformed generated file when using python 2.7
Merge pull request #204 from dhylands/master

Fix malformed makeqstrdata generated file when using python 2.7
py: Implement break and continue byte codes, and add tests.

Also fixes a bug in the for-in-range optimiser.

I hope to remove break and continue byte codes in the future and just
use jump (if possible).
Merge branch 'master' of github.com:micropython/micropython
py: Remove implicit conversion of float to int in mp_obj_get_int().

Addresses Issue #199.
Fix support for STM32F4DISCOVERY
Merge branch 'fix-stm-discovery' of github.com:dhylands/micropython into dhylands-fix-stm-discovery

Conflicts:
	stm/main.c
Second stage of qstr revamp: uPy str object can be qstr or not.
Add Generic Feature Macros to mpconfigport

* Add some generic feature macros to mpconfigport
* Move pin and port definitions from usrsw.c to mpconfigport