Take a hint: an input hint

There's a new #GNOME initiative, and this one's for everyone:

1. Identify entry widgets
2. Evaluate their purpose, and add `input-hints` and `input-purpose` properties judiciously, none is also fine.

Better #Accessibility, better #OSK experience, better software 🙂

https://discourse.gnome.org/t/announcement-input-hints-initiative/19498