Google Code-in

Currently, a challenge host can't edit the challenge start date and end date. This can only be done by EvalAI admin. Add functionality to edit the challenge start date and end date on frontend. Add a check to make sure that challenge end date is always after challenge start date.

Use this(https://indrimuska.github.io/angular-moment-picker/) package for adding date-time support. Please refer the github issue for more details https://github.com/Cloud-CV/EvalAI/issues/1705