Better keyboard support for editing workspaces

[forteller]

Hi. Thank you for your work!

I have a few suggestions for making it easier to use the Edit workspace feature with just the keyboard:

1. When entering the Edit workspace area, your most likely action it seems to me is to edit the name. The text box should therefor be focused automatically. Preferably with the text selected.
2. You should be able to navigate to all elements with Tab: Button for icon chooser, text box, Cancel and Save.
3. When the button for the icon chooser is selected it should be highlighted in some way, and hitting Enter should open it.
4. When the icon chooser is opened the text box should be focused.
5. You should be able to navigate the icons manually with arrow keys. From the text box it would be nice if you could highlight individual icons both by hitting Tab and then by using arrow keys, and also by just hitting the arrow down key to highlight the first icon.
6. Hitting Enter on the highlighted icon should select the icon and close the icon chooser, hitting Esc should cancel the selection and close the icon chooser. Both should get you back to the Edit workspace area, not close it fully, like what happens on Esc in the icon chooser now.
7. Hit Enter while the text box in the Edit workspace area should save your changes to both name and icon, I made a separate issue for this: Hit enter to save new name on workspace #5977

Thank you again! :)