Merge pull request #5 from tobiasandersson/master

Motor controller
fixed bug #4
Merge pull request #6 from mlosch/master

fixed bug #4 (pid, d-term)
first controller adapter
moved topic subscriber class to an .h file
simple forward controller w/o any real controlling
add p controlling
use ok() offered by node
add header for robot constants
cute comments
making constants const
add public function to determine delta ticks to achieve desired rotation
add turn controller
renaming
Merge pull request #7 from mlosch/master

add controller adapter, forward and turn controller.
add turn subscription to adapter
update pid values