Feature request: Keyboard commands for common actions

[devinprater]

Hello. I am a blind user of your app, so use a screen reader, like TalkBack or ChromeVox. While using the app on the ChromeBook, I'd love to be able to use keyboard commands to interact with the comment I'm on, like upvoting, downvoting, or replying. These keys seem to be open for use:

Control + a : Upvote comment Control + z : Downvote comment Control + r : reply to comment

On Android, you could also use the accessibility Actions menu for Reply, upvote, downvote, all that, although the double tap and hold works well too.

[codeofdusk]

See #964 as well for accessibility actions request.

[codeofdusk]

@QuantumBadger might you be able to add this? A few thoughts:

• As not all devices with keyboards have Ctrl keys, I'm not sure that including Ctrl as a modifier key would be best.
• I'd consider this issue blocked by #986 (as in, it should probably be implemented before this).

[codeofdusk]

Also CC @Cguy7777 as I think he has a phone with physical keyboard.