Updated Plants logic. Added Areas: Managed, Succession and Purchasable [WIP].

Signed-off-by: Koen van Lin <koenvanlin@home.nl>
Tidied up the HandlePlants.cs by extending the ParameterPaintPanel.cs.

Signed-off-by: Koen van Lin <koenvanlin@home.nl>
Combined Parameters updated and given a nice editor. Updated the HandleParameters editor.

Signed-off-by: Koen van Lin <koenvanlin@home.nl>