Created header file to store usable constants and other useful stuff for nodes using the motor controller
Added RotationDirection enum and to_string function
Fixed so that other packages can depend on the node header file. Also made constant strings to std::string for concatination
Motor controller now using s8_pid PID controller isntead of own
Restructured include files. Removed unused zero function. Using new s8_pid namespace
Merge branch 'cleanup'