Remove queries at the same time as categories

See https://github.com/marienfressinaud/FreshRSS/issues/625
Fix a bug when $query['state'] doesn't exist

Add a test in addQueryAction().
Refactor removing query by get param

See https://github.com/marienfressinaud/FreshRSS/issues/625
Remove queries at the same time as feeds

See https://github.com/marienfressinaud/FreshRSS/issues/625