* Pressing 'Enter' while the focus is in the tree did not work due to the
  double-click wxWidgets workaround.  Make it work.
* More clearly document what is happening and how it can be tested.

* Manually change fbp file minor version number so dialog could be edited
  with latest release version of wxFormBuilder.
* Give component view panel more weight for improved component view size.
* Add padding around dialog button sizer.

* Improve component chooser redraw to fit in wxWidgets redraw strategies.
* Use LIB_COMPONENT::Draw and LIB_COMPONENT::GetBoundingBox for drawing the
  component
* Make resize redrawing work properly.

* Allow to select units in components that have more than one right in the
  component chooser dialog.
* Keep chosen unit in history.
* Show preview of current component unit as thumbnail image next to the
  description box.
* Fixes lp:1280567