GCS Added custom splash screen class

It shows a progress bar and opaque text background
GCS Hooks up several sources of the gcs to the splash screen text

Also updates some headers and doxygen
GCS - Added image and resource file for the splash screen
Revert "Revert "Merge pull request #730 from kubark42/add-text-bubble-sliders-v2""

This reverts commit 49eacfb523c566fe7d5ce83b4d62d83f5d34cebb.
TextBubbleSlider: removed QDESIGNER_WIDGET_EXPORT
Merge pull request #576 from guilhermito/gcs_splash

Create a splash screen for the GCS
Revert "Revert "Merge pull request #730 from kubark42/add-text-bubble-sliders-v2""

This reverts commit 49eacfb523c566fe7d5ce83b4d62d83f5d34cebb.
TextBubbleSlider: removed QDESIGNER_WIDGET_EXPORT
Merge pull request #739 from TauLabs/lilvinz/fix_730

Lilvinz/fix 730