added filter criteria models

front-api/controllers/filter_criteria.rb

@@ -0,0 +1,20 @@
+get '/filter/section/:id' do |id_s| 
+  # get filter criteria for a section with id
+  FilterCriteria.where(:owner_type => "Section").where(:owner_id => id_s.to_i).to_json(
+    :include => [:filter_criteria_values]
+  )
+end
+
+get '/filter/category/:id' do |id_s|
+  # get filter criteria for a category with id
+  FilterCriteria.where(:owner_type => "Category").where(:owner_id => id_s.to_i).to_json(
+    :include => [:filter_criteria_values]
+  )
+end
+
+get '/filter/subcategory/:id' do |id_s|
+  # get filter criteria for a subcategory with id
+  FilterCriteria.where(:owner_type => "Subcategory").where(:owner_id => id_s.to_i).to_json(
+    :include => [:filter_criteria_values]
+  )
+end