RIO-71 feat(documentation): build sphinx documentation with sbt

- install Sphinx and some additional Python packages first
- configure sbt-site plugin
- document really documentation guidelines
Merge pull request #13 from NohaGamal/master

RIO-71 feat(documentation): build sphinx documentation with sbt
fix(protocol): RIO-41 Unique Error Codes
Merge pull request #14 from HatemAlSum/master

fix(protocol): RIO-41 Unique Error Codes
feat(really-core): Implementation of Get/Read Handler
- Implement 'BETWEEN' operator in RQL
- Implement GET Request Handler
- Implement READ Request Handler
Merge pull request #8 from ashihaby/feat-readHandler

feat(really-core): Implementation of Get/Read Handler
feat(SimpleAuthenticator): RIO-42 Anonymous Login Support
Merge pull request #17 from ashihaby/feat-auth-RIO-42

feat(SimpleAuthenticator): RIO-42 Anonymous Login Support
Impelements and tests delete command in CollectionActor