Pressing [Enter] will close the Dialog.
Added and edited some comments.
Implemented basic elemental mapping.

The GUI is nearly completed and the MLE method works fine. But is is
much to do, like implementing the SNR calculation.
Merge branch 'DriftDetection'

Conflicts:
	EFTEMj/src/drift/DriftDetectionPlugin.java
Merge branch 'ElementalMapping'

Conflicts:
	EFTEMj/src/elemental_map/ElementalMappingPlugin.java