Added discussion create/reply/delete

- Added createDiscussion
- Added replyDiscussion
- Added deleteDiscussion
- Added new tenderUpdate sub-module for handling updates
- Added tests for reply, create, delete discussions
- Updated docs
- Version bump to 0.2.0
Added discussion create/reply/delete

- Added createDiscussion
- Added replyDiscussion
- Added deleteDiscussion
- Added internal tenderUpdate module to handle all post/put/deletes
- Added tests for create/reply/delete
- Updated docs
- Bumped npm version to 0.2