Added plugin maven-jar-plugin in pom.xml to create executable jar using
Maven.
Merge branch 'master' of https://github.com/CTMM-TraIT/trait_proteomics_qc_tool.git
Configured maven-dependency-plugin to add dependency jars
Configured maven-resources-plugin to add resources to the target
directory.
TODO: Make sure to copy resources to proper folder.
Merge remote-tracking branch 'upstream/master'
ChooseMetricsForm:
- Fixed a bug in the createTransferable method: selectedIndex is set again, so it can be used by the exportDone method (I accidentally removed this functionality during an earlier refactor step).
- Simplified some code in the createListModels and importData methods.
- Added some @Override annotations & Javadocs, replaced a few tabs by spaces and fixed some other small issues.

General:
- Moved the METRICS_SEPARATOR and OK_BUTTON_TEXT constants from the ViewerFrame and AboutFrame classes to the Constants interface to make them widely available.