there seems not to be anything family specific about the interrupt vectors of m3 based efm32 systems, thus renaming vector.h to irq.h
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.
