legs: add shortcuts for departure times

This closes #17.

Signed-off-by: diditclear <didyourupgradeclear@gmail.com>
legs: add dow in shortcuts for departure times

I'm not sure if the community will like it, but it seems that entering the time
of the day only is not really meaningful.
As an alternative, we could have two drop-downs, one for the day, one for the hour,
but we'd need to make both fields required, and it seems as much hassle as the original
datetime picker.

See #17.

Signed-off-by: diditclear <didyourupgradeclear@gmail.com>
legs: improve display of upgrade time

Signed-off-by: diditclear <didyourupgradeclear@gmail.com>
legs: hide standby results for now

Signed-off-by: diditclear <didyourupgradeclear@gmail.com>