Full screen documentation confusing, a full screen button would be great.

[Carreau]

This page speaks a bout URL for full screen lab/notebook.

1. The link don't work, they just add an anchor to the current page ...#./lite/lab/index.html.
2. I find it extremely unclear wha it should do.

I think that when launching a lite notebook/lite lab, next to the "Go back" button, we should just have a "Full screen" button that does the right thing. The right things being to be discussed.

[Carreau]

I think we can close as #135 added a button "Open in tab"