py: Put number parsing code together in parsenum.c.
Add basic super() test.
Add arbitrary precision integer support.

Some functionality is still missing (eg and, or, bit shift), and some
things are buggy (eg subtract).
Merge branch 'master' of github.com:micropython/micropython
Add Configurable LFN support to FatFS
Merge pull request #316 from iabdalkader/fatfs_lfn

Add Configurable LFN support to FatFS
stm: Add USART enum for pyboard skin labels.
stm: Make pendsv_nlr_jump work when debugging is enabled.

Stack layout is different when -g used, so need to handle the pendsv
jump differently.  Addresses Issue #315.
Add EXTI support

Revamp usrsw to use new exti code.
Add user switch callback function.
stm: Add option to pyb_usb_dev_init() to use USB HID interface.

With this option selected, only HID on its own works, not VCP+HID.
py: Fix mpn_sub, was increasing wrong source pointer.

Also change int -> machine_int_t where appropriate.
Fix floating point printing of negative numbers in the range (0, -1.0)
Print an error if a non-valid BOARD is specified.
Update LED configuration
Merge pull request #323 from dhylands/fix-float-print

Fix floating point printing of negative numbers in the range (0, -1.0)
Merge pull request #318 from dhylands/exti

Add EXTI support
Merge pull request #324 from dhylands/board-check

Print an error if an invalid BOARD is specified
Merge pull request #325 from dhylands/led

Update LED configuration
stm: Open header file in text mode (in make-pins).
py: Start to implement shl/shr for mpz.  Fix return void.