GitLab

* Add MICROPY_HW_HAS_LCD
* Add MICROPY_HW_HAS_WLAN
* Use feature test macros in main

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

mpconfigport.h is now included by stm32f4xx.h so that all STM files have
access to these defines.

mpconfig.h will automatically pull mpconfigport.h.

A big change.  Micro Python objects are allocated as individual structs
with the first element being a pointer to the type information (which
is itself an object).  This scheme follows CPython.  Much more flexible,
not necessarily slower, uses same heap memory, and can allocate objects
statically.

Also change name prefix, from py_ to mp_ (mp for Micro Python).