Swapped OK and cancel in settings dialog

This causes Enter to save settings, instead of cancelling
Discard changes to settings when cancel is pressed
Merge branch 'ui-changes' of https://github.com/cs136/seashell into ui-changes
Minor settings menu formatting change
Able to reconnect after a short disconnection with the websocket
Merge branch 'ui-changes' of https://github.com/cs136/seashell into ui-changes
Merge remote-tracking branch 'origin/ui-changes' into ui-changes
[frontend] Documentation comments.