Move comment "keyboard shortcuts" setting to comments -> screen options

[lessbloat]

Seems like it would make more sense to move the comment "keyboard shortcuts" setting from "Your Profile" to the screen options pane of edit-comments.php. Something like:

This was recently done on WordPress.com, and a few members of the core team reacted positively (including me, Mark, and Matt).

This goes in line with removing and simplifying options/settings screens in 3.5, so if it has a (simple) patch (soon), it could be considered.

Related: #21414

Played around with this today a bit. A few things:

1) Keyboard shortcuts should live-toggle based on the state of the checkbox.

2) I can't get $.hotkeys.remove() to work, as I think it tries to reach into long-gone jQuery internals. When looking into that, our jQuery Hotkeys plugin is terribly out of date. It is beta 2, by beta 7, it was completely rewritten, and then 3 years ago, Resig rewrote it: ​https://github.com/jeresig/jquery.hotkeys. If we can't hack in a fix to hotkeys, in order to update hotkeys, we'll need to rewrite our table_hotkeys.

I started on the front-end, while Sergey handled the backend. If we can work out how to remove events, we should be able to combine both patches.

Replying to nacin:

our jQuery Hotkeys plugin is terribly out of date.

Related: #19489. Initial attempt at refactoring table-hotkeys.js: ticket:20885:20885.patch​.

This seems like a great thing for 3.6 early, I think. Definitely not as simple as it appears, and I think anything less than having it turn on and off immediately (and without a page refresh) is not worth it.