Added the DELETE method for /admission_results (allowed only for the
admin).


DELETE
http://fii-admis-restservice-dt5dd3kc2v.elasticbeanstalk.com/api/admission_results
403 Forbidden

DELETE
http://fii-admis-restservice-dt5dd3kc2v.elasticbeanstalk.com/api/admission_results
Pragma: admin
204 No Content