Added initializer with no parameters
Finished getPointsToDraw
Altered drawLines to use scaled points
Bug fix - made drawLines() use getPointsToDraw()
Bug fix, formatting fix
Added inherited methods from Moveable, still need to implement.
Removed old code
Added all functionality to IncrementLineChart. NOT TESTED.
Reorganised fields in the inheritance hierarchy. Fixed constructors to
use superclass fields.
Updated example to work with new constructors
Bug fixes. IncrementLineChart now working.