moves humanize_document_type from AdminHelper to UserHelper

spec/helpers/admin_helper_spec.rb

@@ -1,13 +0,0 @@
-require 'rails_helper'
-
-describe AdminHelper do
-
-  describe '#humanize_document_type' do
-    it "should return a humanized document type" do
-      expect(humanize_document_type("1")).to eq "Spanish ID"
-      expect(humanize_document_type("2")).to eq "Passport"
-      expect(humanize_document_type("3")).to eq "Residence card"
-    end
-  end
-
-end