Summer Milestone 3 vnarwal95 Requester Portfolio
In this pull request, I modified the design of requester portfolio to show more information to users to help them better judge the requester. The work was then completed by Aditi Mithal in https://github.com/crowdresearch/crowdsource-platform/pull/255
To support the new front-end, I ave added fields to serializers, made some modification to models, and viewset. Some more minor modifications were done to front-end.