Accounts in list have nicer titles & descriptions.
Only allow editing supported accounts.
Factor out Prefs class.
Fix: do not refresh columns without a refresh interval configured.
Code tidy: final keyword.
Very manual columns pref page, refactor config classes.
Setup imports to internal prefs.
Switch from deck.conf to internal config.
Can re-import config via prefs.
Use dlgs instead of toast so the user has time to read msg.
Fix: empty columns have -1 unread msgs.