Add tax_references, its controller and some basic pages for viewing ref data about taxes.

test/controllers/tax_references_controller_test.rb

@@ -0,0 +1,7 @@
+require 'test_helper'
+
+class TaxReferencesControllerTest < ActionDispatch::IntegrationTest
+  # test "the truth" do
+  #   assert true
+  # end
+end