Merged Update from HeroesGraveDev!

Other changes:
- Added simple custom Tree-Cell-Renderer for Image-Layer-Tree.
Added Properties-Dialog for the Layer-Nodes

Changes:
- Added IFunc interface.to pass around basic methods as objects.
- Added a JTextField extending class, that has a 'onTextChange'-IFunc
action.
- Added Properties-Dialog for the Layer-Nodes
merging