For any command that spawns an editor, tirgger an update on save, not
just on exit.
- :open-editor writes the text field on save
- :edit-url navigates on save
- :edit-url -t opens a new tab on each save
- :edit-command updates the statusbar text on save
- :edit-command --run runs a command on each save
- :config-edit reloads the config on save
Resolves#2307.
Helps mitigate #1596 by allowing users to 'save' partial work, and
notice if there was an error without closing the editor.
8a9b98c2dc