Major security fix.

1. Permission for accessing etherpad service.
2. Mapping of Collaboration System author id, article id, community id and group id with etherpad service author id , pad id, and group id.
3. Session creation for accessing a pad in iframe.
4. Pad can only be created throughy etherpad apis and user are only able to edit it through ifame.

version 1.3

• Publishing workflow for course
• Real time notification of events to all users
• Feeds for community and group
• Real-time collaboratively editing of articles using Etherpad
• Display graphs for:
  • Communities/groups: timeline, most viewed and trending articles
  • Users: status of my articles, recently and most viewed articles

v1.2

• Maintain revisions for articles. Get to know who has changed and when.
• Private and public groups
• Invitation based group membership
• A new resource type called ‘Course’
• Automated shell and ansible scripts for deployment
• Improvements to the user interface