Stock filter (#1376)

* Initial pass at stock filtering

* Rough in filter

* Cleaning up security listing

* Tweak to search function

* Combobox tweaks

* Clean up search query

* Update trades test with combobox

* Update securities.yml

app/controllers/account/trades_controller.rb

@@ -33,6 +33,10 @@ class Account::TradesController < ApplicationController
     end
   end
 
+  def securities
+    @pagy, @securities = pagy(Security.order(:name).search(params[:q]), limit: 20)
+  end
+
   private
 
     def set_account