MBS-3862: Do not reveal editors email address when sending private messages

When a private message was sent, and a carbon copy was sent to the original
sender, the other editor's email address would be revealed. Instead of sending
one email, 2 emails are now sent, to avoid this happening.
Add References and In-Reply-To headers to personal correspondence emails

The message ID is simply the current time when the email was sent, but as the
system never needs to reference this ID, it seems ok that we can't reference it
again in the future. This should result in email clients grouping further
replies.
Move t/email.t to t/lib/t/MusicBrainz/Server/Email.pm, run as part of t/tests.t.
Move t/email/NewReleases.t to t/lib/t/MusicBrainz/Server/Email/NewReleases.pm.
Move t/email/Subscribtions.t to t/lib/t/MusicBrainz/Server/Email/Subscriptions.pm.
Move template_macros.t to lib/t/TemplateMacros.pm.
MBS-3862: Maintain correct threading when messaging other editors through the website
Merge branch 'mbs-3862'

* mbs-3862:
  MBS-3862: Maintain correct threading when messaging other editors through the website
  Add References and In-Reply-To headers to personal correspondence emails
  MBS-3862: Do not reveal editors email address when sending private messages
Merge branch 'master' into move-tests

* master: (36 commits)
  MBS-3862: Maintain correct threading when messaging other editors through the website
  Add a beta cron script
  Re-add Historic::Relationship file
  Remove all the old edit migration code, this will never be called again
  Move t/z_sql.t to a t/tests.t test
  Move t/ws-1-search.lwp-mock to t/lwp-sessions
  Move t/validation.t to a t/tests.t test
  Fix EditRegistry tests
  Move t/z_editqueue.t to a t/tests.t test
  Move z_edit_differences.t to a t/tests.t compatible test
  Move t/i18n_link_expander.t to t/tests
  Move t/form* tests to t/tests.t compatible tests
  Remove disabled tests
  Remove old t/controllers/ test launchers
  Move data_wikidoc.xmlwebservice mock to lwp-sessions
  Move unaccent.sql tests to PGTAP
  Move t/coverart_regex.t to Data::CoverArt tests
  Move context.t to t/tests.t
  Move cachemanager.t to t/tests.t
  Move all tests in t/actions to proper tests.t tests
  ...

Conflicts:
	t/email.t
	t/tests.t
Merge branch 'move-tests'

* move-tests:
  Move template_macros.t to lib/t/TemplateMacros.pm.
  Move t/email/Subscribtions.t to t/lib/t/MusicBrainz/Server/Email/Subscriptions.pm.
  Move t/email/NewReleases.t to t/lib/t/MusicBrainz/Server/Email/NewReleases.pm.
  Move t/email.t to t/lib/t/MusicBrainz/Server/Email.pm, run as part of t/tests.t.
Use carton to run daily and hourly cron jobs
These settings get the logs to be quiet, but they might be overkill.
So far, no adverse memory footprint issues, so I'll go with it for now.

Conflicts:

	admin/nginx/nginx.conf
Add full stacktraces to processes that time out
Include a stack trace in error pages

Conflicts:

	lib/MusicBrainz/Server.pm
	root/main/500.tt
Fix unique primary aliases per locale

The original trigger was intended to set the primary column to 'false' when a
new primary alias was added for that artist, with a given locale, but due to a
bug it was setting primary to false for *all* aliases with that locale, over all
artists.

The trigger has been fixed now, and verified correct with pg_prove (see
t/pgtap). Sadly the trigger functions have got a little more complicated due to
the somewhat restrictive nature of plpgsql.
Fix the delete_unused_urls pgtap test
Add pgTAP to carton.lock
Include recent changes to t/email.t in t/lib/t/MusicBrainz/Server/Email.pm.
Remove double "use Encode" in Server.pm.
Merge branch 'from-production'

* from-production:
  Remove double "use Encode" in Server.pm.
  Include a stack trace in error pages
  Add full stacktraces to processes that time out
  These settings get the logs to be quiet, but they might be overkill. So far, no adverse memory footprint issues, so I'll go with it for now.
  Use carton to run daily and hourly cron jobs