New event

Implemented create event methods
save and back button added

Added save button and made back button working
DatePicker Input

Created Datepicker input and saving of new events in model
Merge branch 'create_event' into development

Conflicts:
	app/src/main/AndroidManifest.xml
	app/src/main/java/com/bdlabs_linku/linku/EventsFragment.java
	app/src/main/res/values/strings.xml