Blanket wide to all .c and .h files. Some files originating from ST are
difficult to deal with (license wise) so it was left out of those.
Also merged modpyb.h, modos.h, modstm.h and modtime.h in stmhal/.
Main reason for expanding buffer protocol API was to support writes to a
buffer in ADC module (see read_timed). With this change you can now
create an array of arbitrary type and ADC.read_timed will store into
that array in the correct format (byte, int, float). I wonder though if
all these changes were really worth it to support just this function.
Hopefully this enhanced buffer protocol API (with typecode specified)
will be used elsewhere.
