Add markdown cache columns to the database, but don't use them yet

This commit adds a number of _html columns and, with the exception of Note,
starts updating them whenever the content of their partner fields changes.

Note has a collision with the note_html attr_accessor; that will be fixed later

A background worker for clearing these cache columns is also introduced - use
`rake cache:clear` to set it off. You can clear the database or Redis caches
separately by running `rake cache:clear:db` or `rake cache:clear:redis`,
respectively.

1 files changed, 4 insertions, 0 deletions

diff --git a/spec/models/abuse_report_spec.rb b/spec/models/abuse_report_spec.rb
index 305f8bc88cc..c4486a32082 100644
--- a/spec/models/abuse_report_spec.rb
+++ b/spec/models/abuse_report_spec.rb
@@ -9,6 +9,10 @@ RSpec.describe AbuseReport, type: :model do
   describe 'associations' do
     it { is_expected.to belong_to(:reporter).class_name('User') }
     it { is_expected.to belong_to(:user) }
+
+    it "aliases reporter to author" do
+      expect(subject.author).to be(subject.reporter)
+    end
   end
 
   describe 'validations' do