Add a hidden input:submit field in facets form (closes #1988784) <Enter> is supposed to submit the form only if there is a single input:text field. However most browsers will submit the form on <Enter> anyway if there is an input:submit field. see: http://www.w3.org/MarkUp/html-spec/html-spec_8.html#SEC8.2 Firefox 7.0.1 does not submit form on <Enter> if there is more than a input:text field and not input:submit but does it if there is an input:submit. IE 6 or Firefox 2 behave the same way.

AnyRsetView: Refactor the columns_name method and update doc. We drop the 'label_column_%s' % colidx pattern and add a clean column_label method that might be overwritten by children class to alter the way default columns headers are computed.