Template treeview width

[franbarra]

On the Create a new document from template the templates treeview object has incorrect width. Once you click on Add, and Esc from writing anything, the treeview will resize to the correct width.

** Steps to reproduce **

1. Open a new instance of Gummi
2. Click on File option and then, New from template
3. Click on Add
4. Press Esc without writing anything.

** Platform **

• Ubuntu 18.04
• Gummi 0.8.1 compiled from source

Steps:

Result: