Simplified code
Added interface fr.ritaly.dualcommander.HasParentDirectory
Moved class FileComparator to its own file
Renamed class fr.ritaly.dualcommander.FileList.FileRenderer into FileListCellRenderer
Added renderer class fr.ritaly.dualcommander.FileList.FileTableCellRenderer
Made the buttons non focusable
Populate MANIFEST entries at build time
Added a file 'application.properties' whose properties are populated at build time
Added methods to retrieve the version & release date from the resource file 'application.properties'
Display the application version in the main frame's title
Render the file entries with a gray color (to distinguish them from the directories (in black))
Improved rendering of selected lines
Improved ergonomics by auto-selecting entries when navigating between directories