ipc_pingpong: start receiving thread immediately

Rationale: When using `msg_send_receive()` the receiving thread needs to
be already in receiving mode.
Merge pull request #907 from OlegHahm/ipc_pingpong_fix

ipc_pingpong: start receiving thread immediately
Merge pull request #908 from LudwigOrtmann/make_msb-430-common_programmer

make: clean msb-430-common Makefile.include
msp430: remove expensive modulo call
msp430: show overflow counter in hwtimer debug
msp430: handle hwtimer interrupts correctly
msp430: fixed typo and comment style
cc430: adapted msp430-hwtimer fix to cc430
msp430: add timer debug
test_hwtimer: hwtimer is automatically initialized now
msp430: don't enable Timer 0 by default
cc430: checking for the TAIV number

Checking for the TAIFG seems not working here.
msp430: cc430: unify number formats