Allow making the current view take the whole application size (and go back to previous view)

Submitted by Thibault Saunier

Description

We should be able to focus on the current view, for example, I have a splitview and am editing one file, I want to focus on that file and hide everything else (even the various sidebars etc..) I should have a way to do that with one key binding. Then if I want to go back to previous view I should re enter the same binding an be back in the previous view.

For vi the key should be <ctr>w+o