Added unit test for filter
Added unit test for filter

sigmoidanalytics/spork,siddaartha/spork,siddaartha/spork,sigmoidanalytics/spork,siddaartha/spork,siddaartha/spork,siddaartha/spork,sigmoidanalytics/spork,sigmoidanalytics/spork,sigmoidanalytics/spork,sigmoidanalytics/spork,siddaartha/spork