Changed layout of qttablayout from expanding to minimum, will usually
leave more room for the canvas.
Removed padding around canvas when perf-mode is enabled.
added setPadContents flag to GUI container classes
Made ElementGroup look a bit more traditional, i.e. standard bevelled
look instead of flat.
Merge pull request #102 from sintefmath/cdyk_gui_qtlayout_fixes

Merging cdyk_gui_qtlayout_fixes, fixes some issues in the qt layout (expanding tabs) and makes padding of layout contents optional.