exclude ``ipv6_iface_set_routing_provider()`` from ``#ifdef MODULE_RPL`` so that other routing protocols can use it too.
Make hwtimer_spin() work even with interrupts disabled
by using only 16 significative bits on MSP430 hardware timers
Reduce variable scope in init function
samr21: implemented 32 bit hwtimer
Merge pull request #1998 from Troels51/samr21-hwtimer-fix

samr21: 32 hwtimer
Merge pull request #2212 from Lotterleben/fix_ipv6_iface_set_routing_provider

exclude ``ipv6_iface_set_routing_provider()`` from ``#ifdef MODULE_RPL``...
Merge pull request #1619 from rousselk/msp430-hwtimer-16bit

Only use 16 significative bits for MSP430 hwtimers