Code style fixes to the AVRISP-MKII Clone programmer project.

git-svn-id: http://lufa-lib.googlecode.com/svn@2562 d5102386-fcda-11dd-9fdb-3debd5008f28
Fixed bug in the TWI peripheral driver for the AVR8 devices causing incorrect failure codes to be returned in some cases (thanks to Peter K).

git-svn-id: http://lufa-lib.googlecode.com/svn@2563 d5102386-fcda-11dd-9fdb-3debd5008f28