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.
Btw, I mean a normal ExtJS event (e.g.: https://github.com/aodn/aodn-portal/blob/master/web-app/js/portal/ui/search/SearchFiltersPanel.js#L155 ) rather than using `Ext.MsgBus` (these should be reserved for "global" events that lots of components will be subscribed to).