make: added targets 'debug-server' and 'reset'

- added targets to Makefile.include
- added DEBUGSERVER and RESET vars to Makefile.vars
- added output of those to Makefile.buildtests
boards/stm32fXdiscovery: added debug-server target

added "make debug-server" target for
- stm32f0discovery
- stm32f3discovery
- stm32f4discovery
make: msb-430 boards: added debug and debugserver targets
Merge pull request #1542 from haukepetersen/add_make_moretargets

make: added targets 'debug-server' and 'reset'