Trying to get rid of unresolved symbols message
Encoders PPR moved to Preferences

PPR=0 means the encoder is disabled.
Sometimes we can use one encoder on chassis, e.g. to get distance the
robot traveled, not precise but close enough.
Robot::init() for robot prefs init
Moved reading DigitalInputs to a UTest command

Cleaned up JoystickShoot a little.
Vectorized the content of UTest class to make it more "dynamic" - add
more unit tests!
Tested and debugged on #2

The sequence of what inits first and what does after is important.
UTests can initialize only after all subsystems are constructed.
Whitespaces seem to be not allowed characters in the Preferences.
Merge remote-tracking branch 'origin/master' into LogSubsystem

Conflicts:
	CommandBasedRobot.cpp
	Commands/DriveStraight.cpp
	Commands/JoystickShoot.cpp
	Commands/JoystickTank.h
	Robot.h
	Robotmap.h
	Subsystems/Chassis.cpp
	Subsystems/Chassis.h
	Subsystems/VelocityController.cpp