Fix auto-selecting title item on editing Event screen appearance.

Still broken due to start date not being
normalized.
Fix auto-selecting title item on editing Event screen appearance.

Still broken due to existing start date not being
rejected for the later title item if not actually
a later date.
Fix auto-selecting title item on editing Event screen appearance.

Still broken due to item for existing date being
selected without using existing date.
Harden EventManager saving by normalizing start date.