* Checking for the last date in the event series before deleting a date. Last date in a event series should never be delted.
* Adding check to ensure that last date in a event series is not deleted. Editing unit test around deleting subevent to assert on alert-danger
* Increasing the scope of test_delete. We are now creating 2 subevents and testing deleting one and ensuring that the last one is not deleted
* Fixing alert text. Removing a redundant if condition for checking subevent count
* Adding assert for second event to ensure its not deleted
* Minor fixes and rebase
