Scaffold out basic transactions model and UI (#478)

* Transaction scaffold

* Rough in transaction views

* Fix sort order

* Fix mass assignment issue

* Fix test

* Simplify CI workflow

* Don't seed db before test

test/models/transaction_test.rb

@@ -0,0 +1,7 @@
+require "test_helper"
+
+class TransactionTest < ActiveSupport::TestCase
+  # test "the truth" do
+  #   assert true
+  # end
+end