add trigram index to user names

db/migrate/20170117233040_add_trigram_index_to_users.rb

@@ -0,0 +1,6 @@
+class AddTrigramIndexToUsers < ActiveRecord::Migration
+  def change
+  	execute "set statement_timeout = 0"
+    execute "create index index_users_on_name_trgm on users using gin (lower(name) gin_trgm_ops)"
+  end
+end