Refactoring ideas to discuss

Please add your opinion below the suggestions.

• Rename /icons to something more applicable, because there are by far no longer only icons in there. ==> done in [469] and other changesets of #159
• Change package de.jacavi.rcp.dlg to .dialog. ==> done in [513]
• Make sure all views have the postfix -View, all dialogs have the postfix -Dialog, etc. ==> done in [514]
• Move classes that aren't related to the TrackWidget out of de.jacavi.rcp.widgets.controls. ==> done in [515]
• Rename project 'JACAVI' to the common spelling 'JaCaVi'.