* Make input/widget conversion sub-menus optional
* Improve input/widget conversion sub-menu text
- Fix incorrect text for conversion from widget to input, previously it
effectively said "convert input to input"
- Use "input" instead of "🔘". The former is clearer and consistent
with the rest of the application.
- Use title case (consistent with the rest of the menu entries).
- Strip the trailing periods. There is already a visual indicator for
sub-menus, and no other sub-menus use trailing periods.