Split platform-dependant definition in different header files

- platforms/standard -> Arduino UNO / Duemillanove boards
- platforms/mega -> Mega board
Refactored and fixed logging 

- writing in file is now done just after the opening 
- file is closed immediately after writing
Fix project properties

- Unexpected resets, suspected to be induced by build, no longer occur
Fixed LED wiring in defs

- Sparkfun microSD shield uses pin 8 for CS, so orange LED has been
rewired to pin 10