add new fields to notification authoring

Here are some ideas to date. Are there others?

New fields for all notifications:
• Contact person
• Link
• For required: Consequences for not completing task/attending event

New fields for events:
• End date
• End time
• All day event

Add these to email-out content, and to .ics files.

For UI sketches, see these two links:

https://confluence.media.berkeley.edu/confluence/display/MYB/Notification+Authoring+-+Events+End+Time+and+Date%2C+0.5

https://confluence.media.berkeley.edu/confluence/display/MYB/Notification+Authoring+to+Notification+Receipt+-+Contact+Person%2C+Link+and+Consequences