Add search button to Concept search

We need a search button next to the concept search field which triggers search when clicked or when 'enter' is hit. Ideally either of these methods of explicitly submitting the form (as opposed to the automatic searches that happen after a delay in typing), would create an entry in the browser's history for the search phrase, so pressing the back button would show the last explicitly submitted search results.

We will need to include the documentation for the new option for displaying the enter button on this page