* UDP currently not supported
 * As there is no way (that I know of) the espconn_regist_connectcb()
   callback can recognize on which socket has the connection arrived,
   only one listening function at a time is supported

Addresses issue #1203.

Refactored from "stm" module, provides mem8, mem16, mem32 objects with
array subscript syntax.

Remove unused and unneeded functions, also create Pin.get_config() that
returns the whole configuration of the pin.

This reduces code size by ~500 bytes.

This is consistent with the logic in mp_get_buffer, and the code here is
an inlined version of that function.

- by default look for a user.props in the msvc directory, which is more convenient
  than the built-in way of looking for such file in the user's home directory
- make git ignore the file

This one creates a semaphore, therefore it must be executed only
after a hard reset (or when coming out of hibernation).

While in STA mode isconnected() returns True when connected to an AP
and the IP has been acquired. In AP mode, WLAN.isconnected() returns
True if at least one connected station is present.

This allows errors to be seen and prevents hanging
the board from doing: pyb.disable_irq()

Can complete names in the global namespace, as well as a chain of
attributes, eg pyb.Pin.board.<tab> will give a list of all board pins.

Costs 700 bytes ROM on Thumb2 arch, but greatly increases usability of
REPL prompt.

Also rename py-version.h to mpversion.h for consistency with mpconfig.h.

Each result is displayed like this:

ssid='MySSID', bssid=b'\xc0J\x00z.\xcc', security=2, channel=None, rssi=-74

The CC3200 doesn't provide channel info, that why is 'None'.

Just for consistency.

This is actually a workaround Ter Term's issue of not obeying to the
telnet options that the server is sending. Therefore, we must buffer
chars until either a '\r' or the max length of the username/password
is received.

This makes sense since only WLAN is supported here.

This doesn't handle case fo enclosed except blocks, but once again,
sys.exc_info() support is a workaround for software which uses it
instead of properly catching exceptions via variable in except clause.