In preparation for another command I'd like to make I've first got to
make a place where Invites live.

There's probably other parts of the code that interact with Invites that
I've missed, but this is a good start at least.

It used to handle the initial failure differently than internal failure.
Now I've moved the outside bits inside, so it can run again when it
encounters an unknown character.

* policy:
  Show FUP before starting registration in earnest

Disabling the Bandwidth transcription in the process

So that singletons can be added, for example

Explicitly return true to avoid passing to next link in the tree.  Make sure
command stanzas fulfill both command and iq manager if needed.

* dry-sentry:
  DRY up sentry and logging

* vcard4:
  Switch TTS OGM from vcard-temp to vcard4 PEP

Wrap every blather handler in sentry setup and exception capturing so each route
doesn't have to handle it seperately.

panic is a last resort, usually better to return an XMPP error and report/log,
so default to that.

Also wraps each handler in a span. Note that for multistage command handlers
this span is too long and they will want to call finish/set_span internally.

* background-log:
  Log in background thread
  Don't run our whole app in an at_exit

File IO is fast, but can still block reactor.

We don't use much of it, and this makes using other at_exit hooks more realistic.

* new-blather:
  Update to latest blather upstream
  notify_customer helper

See: https://github.com/minitest/minitest/issues/912

Which has merged our changes

Makes the number of users to do on startup much smaller and slower-growing.
Expired users have been told about their low balance quite a bit already, and
will be notified by billing cronjob etc from here out.

The bitfield bit 1 was used by a different project (sgx-catapult, see:
https://gitlab.com/ossguy/sgx-catapult/-/commit/459d7d1dfe208db1708f1d648b82b38c002ad35a).
This other project no longer uses the bit, and in fact that whole project is
dead and gone, but if you previously ran that project against the same redis
that you now run this project against then please make sure you have zeroed-out
that bit first.

You can verify using this script:

    redis = Redis.new
    redis.keys("catapult_settings_flags-*").each do |k|
      p redis.getbit(k, 1)
    end

* snikket:
  Initial bare-bones admin command for launching a snikket instance

* limit-credit-card-amount:
  Limit size of credit card transaction by trust level

* limit-top-up-take-2:
  Only one credit card transaction per customer per day

This reverts commit 7a28753d7df5d7d6f5f890d302634b1bdbd25f73, reversing
changes made to e4ec9b8eb368ed0997887ebd99f8c79982640d20.

* limit-top-up-freq:
  Only allow one credit card transaction per customer per day