Allow configurating the viewport

[trungleduc]

Always displaying the transform control makes it easy to accidentally move the objects while rotating the camera. Other CAD software do not activate the transform control by default. I think we should follow this behavior.

Since we had already the dialog to show and hide the axes helper, we can change this dialog to a viewport config dialog with the following items:

• Toggle axes helper
• Toggle object highlight mode: using a bounding box or using highlight color
• Highlight or bounding box color selector
• Viewport background color, it would be great if we could support gradient color.

We could reuse the setting system of JupyterLab to persist the viewport config.

[martinRenou]

Agreed! A simple toggle button like the wireframe may be enough

[arjxn-py]

Makes Sense! Will be happy to do it :)

[trungleduc]

I updated the issue about the viewport config. The transform control merits its own toggle button on the toolbar