Issue 1315

Id's are removed as this components are now being used more than once.
The on enter key action is replaced with a traditional button that becomes active when the user enters both values. The error labels are now redundant.
Any reason why we need a "go" button - can it not be done on the fly like before?  Most other things (e.g. the subset/filter controls) cause updates to happen immediately without having to click a button...