Feature/timeline crud

Implemented adding new events to the timeline.

Some UI thinkg are still missing, like disabling "addEvent" button before dataSet is loaded etc.

First I would like to modularize everything: separate eventLoadingForm, newEventForm or something like this.

Please don't merge until not finished by me :P
I will just put input id here for now.

I guess there will be only one such input for handling loading multiple data from server, so id is better than just classes.