Caching recent searches for autocomplete

Added new panel at autocomplete with recent searches, minlength for
autocomplete changed to 0, but will do request to database only if 2+
chars in string. also did little changes at jquery.tagsinput
Is there a reason you changed these? I want to check if `restrict_to` is sent to `getResults` or not. The way you did it would fail if for instance (in another function) we got the value `false`, `""` or `0`. I recommend using `?` when checking if variables are defined. See http://coffeescript.org/#operators under *The Existential Operator*