Update README.md

Removed the sensio insight label until they fixed the issue with "use" & annotations.
Added exception throwing
Added tests
Make sure we are only accept exception baseclasses
Added documentation
Added latest symfony versions
Merge branch 'master' of github.com:jaytaph/RateLimitBundle into exception
Removed 2.6 tests for now
Merge pull request #16 from jaytaph/exception

Exception