backported RTC_Alarm function in st stdlib needed by OpenWSN iot-lab_M3 BSP
Merge pull request #30 from thomaseichinger/stm32f103rey6_rtc_alarm

stm32f103rey6: backported RTC_GetAlarm function in st stdlib
stm32f103_rey6: implement std periph driver
updated to newst version of @haukepetersen's definiton
changed ARCH_MAXTIMERS to HWTIMER_MAXTIMERS
handle `TIMER_UNDEFINED` of `tim_t`
replace $(MAKEBASE) with $(RIOTBASE)