Improve UX on the draw selection settings

[damienmarchal]

1. Restore visualisaion of the Scenegraph when the application opens.
2. Implement a load/store mechanism to save visualization of the selection state
3. When the interactive mode is not enabled... gray out the Viewer's parameters and shows a tooltip explaining how to activate.

[hugtalbot]

Hi @damienmarchal
thx for the PR, the scene graph was broken in Qt ?
Load/store mechanism to save visualization would be nice in ImGui

[damienmarchal]

@hugtalbot Not really broken, but the scene graph was not the selected tab by default at runSofa startup (which it was before)

About the save/load of the camera view... I think a more general saving of per-scene editor settings would be nice in imGUI and Sofa.Qt.

Of course this shouldn't be mixed with the fact that an in-scene camera positioning should also be possible.

[damienmarchal]

Passed to ready, I'm happy :)

[damienmarchal]

Ready... so merge :)