Changed Arduino Sensors to Functions
deleted comments with Rudi
changed brick + category colors
Merge remote-tracking branch 'origin/arduino_functions' into arduino_refactoring

Conflicts:
	catroid/src/org/catrobat/catroid/arduino/ArduinoIncomingPinData.java
	catroid/src/org/catrobat/catroid/arduino/ArduinoSensor.java
	catroid/src/org/catrobat/catroid/formulaeditor/SensorHandler.java
	catroid/src/org/catrobat/catroid/stage/PreStageActivity.java