Partially fix #254

- getRivers nos support from (default is 0) and size (default is 10) url
parameters.
- The UI still need to be updated.
Update Admin UI dependency versions

- Angular 1.2.10
- Angular UI 0.11.0
- Boostrap 3.1.1
Probably fix RiverMongoMapReduceTest

- There is no reason to use drop_collection = true in this scenario
Fix few exceptions thrown during unit tests