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/.
Improved the Thumb assembler back end. Added many more Thumb
instructions to the inline assembler. Improved parsing of assembler
instructions and arguments. Assembler functions can now be passed the
address of any object that supports the buffer protocol (to get the
address of the buffer). Added an example of how to sum numbers from
an array in assembler.
