Clear password input on Ctrl+Backspace

[holykol]

See the title. Some users would also expect input to clear itself after holding backspace for some time (e.g. 600ms).

[aarongable]

Agreed, this would be nice.

I will note that there are three other key combinations which clear the input already:

• ESC
• Ctrl+C
• Ctrl+U

I'll also note that key-repeat (which would allow holding backspace to delete multiple characters in rapid succession) has been landed on master but not yet included in a tagged release.