Filter by category alignment is off by 2 pixels

While here, maybe check the capitalization of the filters
"Filter by category" is consistent with other filters in Core
but is the capitalization of "Maintenance Status" correct — should it be "Maintenance status" ?

Corrected filters display by removing the fieldset. We discussed with Chris if we should remove the field set from the one field or add fieldsets to the other three filter items. We also located a single piece of CSS that set margins to 0 for this single item.

Latest commits fix nightwatch test errors for filters on the browse page. Added rewrite of filter labels on the browse page to use sentence case. All tests passing now and MR is ready for review.

Though a double-scoped issue, I'm happy to have it in. Thanks for your contributions here at NEDCamp!