Added test case for language_s param
Fixed issue with challenge not being filtered by facet, modified test
case to cover the context.
Revert "Fixed issue with challenge not being filtered by facet, modified test"

This reverts commit c53fbfdf776cb57eb9071a5c9383e6cd927a50b0.
Fixed Challenge filter issue.
Merge pull request #22 from pradhanta/master

Added test case for language_s param