Hide Sidebar Elements

[ElykDeer]

I'd like to be able to hide sidebar widgets I'm not using. I never use the memory map, for example, and it'd be nice to reduce the number of icons I have in the sidebars.

This would also allow us to easily hide the external links icon when not working in a project.

My QT-fu couldn't accomplish this either. It seems the icons themselves don't support hiding, and it seems the all the sidebar widgets reimplemented .hide() to minimize the sidebar instead of just not rendering.