Optimised region filter, to minimise db requests

app/views/regions/_filter_region.haml

@@ -18,10 +18,11 @@
       = filter_region.name
       - if session[:region] == filter_region.id
         %em.fa.fa-times
-      - elsif filter_region.regions.present?
+      - elsif !filter_region.region && filter_region.regions.present?
         %small
           %em.fa.fa-chevron-down
 
+  - unless filter_region.region
     %ul
       = render partial: '/regions/filter_region',
         collection: filter_region.regions