Editing

[heyhuyen]

Should be able to edit

• the title and dates for a trip
• be able to delete a trip
• add/remove place items from a trip
• edit/delete media from place items

[heyhuyen]

I'm going to add separate issues for:

• Editing start/end dates (can be part of implementation of #30 )
• Editing trip titles (low priority? do we still want this?)
• Adding more story places after a trip has been created from the story activity (will be done part of #31 or #46)
• Edit/delete "photo" media items (#52 )