Added 'drivers' directory, intended to hold code for specific hardware.
drivers: Initial import of WIZnet5x000 driver.
drivers, wiznet5k: Fix IP addr verification.
drivers, wiznet5k: Change SPI interface to read/write multiple bytes.
drivers, wiznet5k: Add W5200 support.
drivers, wiznet5k: Properly fix ARP bug with W5200 chipset.
drivers, wiznet5k: Add HAL_Delay(1) to "infinite" loops.
drivers, wiznet5k: Make DNS service use HAL sys tick.
stmhal: Add wiznet5k module, to control WIZnet ethernet adaptor.

Allows to create socket objects that support TCP and UDP in server and
client mode.  Interface is very close to standard Python socket class,
except bind and accept do not work the same (due to hardware not
supporting them in the usual way).

Not compiled by default.  To compile this module, use:
make MICROPY_PY_WIZNET5K=1
stmhal, modwiznet5k: Add very minimal documentation.
msvc: Exclude modtermios, include extmod and fix compilation error
Merge branch 'msvc-extmod' of github.com:stinos/micropython into stinos-msvc-extmod
extmod: Fix type-punned-ptr error.
Merge branch 'stinos-msvc-extmod'
py: Make import recognize and load native modules (.pyd or .so files)

Simply check if a .pyd or .so file exists on the Python search path
(if a .py file if not found) and call a function to get a module from it.
Implement this LoadDynLib function for msvc.
msvc: Build seperate micropython dll and executable

- export some core functions using exports.def, export constants/data using the
typical dllexport (exporting data using .def file yields multiple copies of data).
- rename micropython project to micropythoncore and have it produce a dll + impor lib
- add new micropython exe project (which just calls the exported main from the dll)
- add property sheet for external modules
Disable stack check