RIOT-OS/RIOT — pull request #1865 by haukepetersen (2014-10-23 16:09:36+00:00)
Title: cpu/stm32f0: optimized GPIO driver implementation

Tried a different concept for handling the GPIO-pin-and-port mapping (thx to @HexLuthor for the idea!).

The code is tested with `test/periph_gpio` and `tests/periph_gpio_int` and seems to work as before. The importent thing is the memory usage:

before applying this PR for `tests/periph_gpio`:
```
text data bss dec hex
17440 112 4280 21832 5548
```

and after:
```
text data bss dec hex
16428 112 4280 20820 5154
```

--> saves 1Kb of flash and makes the code a little less ugly...