Events editing doesn't work if the date and time aren't changed

[anna-otrokhova]

Could you please check it @robtweed ?

We noticed that if we edit Events heading and change any other fields besides date and time we get "events saved" but actually they aren't updated, they can be updated only if date and time are modified too. (It works for any fields on React version)

http://prntscr.com/iepsvd
http://prntscr.com/iept61

Relaed issue: PulseTile/PulseTile-AngularJS#74