Restructure Arduino code

[jeroendoggen]

The 'serialPacket" class is too big...

Split up the code with some subclasses, polymorphism,...? (todo: think about a good structure)

Class SerialMessage

• class Communication

  -- class Sender

  --- class sendCommands

  --- class sendData

  -- class Receiver

• class Actions

[jeroendoggen]

More info in: d1e343caae5bd04fd6b60dbf10b7adb4b5dfea55 (in "refactoring" branch)