also, the whole gpio header file is now a big doxygen group, structuring the convenience functions and the register/value definitions
includes minor refactoring in example code and modification of how the generic and the tinygecko specific vector.h go together (bringing it in line with stm32/f1's memorymap.h)
unless sources are explicitly given, the linker scripts and make files were copied over from the stm32/f1 port.
