added board airfy beacon
cpu/cc2538: Enable the CC2538's more compact alternate interrupt mapping.
Merge pull request #1930 from locicontrols/cc2538-altmap

cpu/cc2538: Enable the CC2538's more compact alternate interrupt mapping.
Merge pull request #1896 from mehlis/add_board_airfy_beacon

added board airfy beacon
cpu/stm32f1: fixes for the cpuid driver
added new board f4vi1
Merge pull request #1931 from thomaseichinger/stm32f1-cpuid

cpu/stm32f1: fixes for the cpuid driver
Merge pull request #1933 from StefanPfeiffer/add_board_f4vi1

board: added support for f4vi1
boards: adjusted TIMER_0 defines for NRF based b.

adjusted for
- pca10000
- pca10005
- yunjia-nrf51822
cpu/nrf51822: fixed timers

- changed TIMER_0 to be a 24-bit timer -> see Nordic PAN #32
- cleaned up timer initialization code
- added check if an interrupt channel was active