Provide alternate write-in keyboard layouts

[beausmith]

Moving comment from @whitneyq on https://github.com/votingworks/bmd/issues/333 here to new issue:

I'd be happy to talk about alpha vs. qwerty layout considerations if you're interested. We did a little research on this for the VVSG work. Two bottom lines:

• People who know keyboards can navigate ALPHA layouts but prefer QWERTY
• People who don't use computers or don't read well prefer ALPHA

Existing systems: Switch order is alpha in all current systems. One existing system has a QWERTY layout, but does switch access in ALPHA order, and confused everyone (except totally blind voters). One has a option to switch between the two (I can't remember how this was done, but I think it was a system that required access switches to be activated [boo] so it was tied to that preference option)

Also, Denis Anson has been noodling on how to do keyboard entry a lot, so we had him talk about his ideas in the videos

Additional Notes

• Providing a toggle to allowing a voter to toggle between alternate keyboards is possible and not difficult.
• In user test with (sighted but no mobility) voter, they mentioned that their they would prefer: row, group, key select. However voter said that because adding a write-in would be a seldom used feature, it was acceptable to have to navigate back and forth through all keys.
• The keyboard library we are currently using (simple keyboard) has an extension to allow up/down/left/right navigation to the most logical key.

[whitneyq]

Thanks. Makes more sense in its own thread.