v1.3: New features and many bug fixes.

New features include:
- file.flush, os.stat
- unicode enabled by default on unix and stmhal ports
- print function accepts file= argument
- I2C object allows for 16-bit mem addr
- emergency exception buffer for improved exception traceback
- USB_VCP object
- 0:/ and 1:/ changed to /flash and /sd
- improved Pin object
- can set pin alternate function from Python
- builtin reversed, can len() and subscr range objects
- added moductypes
- added modzlibd for DEFLATE decompression

Code improvements include:
- more efficient line-number to bytecode mapping
- new STM HAL driver v1.3.0

Bug fixes include:
- mpz (bignum) fixes
- accel startup improved
- important bug fix in GC

v1.2: Unicode support (disabled by default); bug fixes and minor feat…

…ures added.

v1.1.1: Improved LCD driver, UART REPL and some bug fixes.

Bumping version because this binary will be put on the next batch of pyboards.

v1.1: Many bug fixes, enhancements and features.

v1.0.1: mostly bug fixes for stmhal/, features for py/.

Main bug fixes: flushing USB CDC correctly, setting RTC.

Main features for stmhal: improved native and viper emitters.

This version goes on the next batch of pyboards.

Version 1.0! This is shipping with the next batch of pyboards.

Preparing for v1.0.