Restore tab widgets in ImageEditor + minor fixes
Pass Qt version to ImageViewer
Merge branch 'update-image-editor'

* update-image-editor:
  Pass Qt version to ImageViewer
  Restore tab widgets in ImageEditor + minor fixes

Conflicts:
	Applications/ImageEditor/QtImageEditor.cxx
	CMake/Superbuild/ExternalProjectsConfig.cmake
Merge pull request #344 from finetjul/update-image-editor-rebased

Update image editor