adds another cert for pycbclive, and removes alex nitz's email

fixed links to new computing repos, adding gdpr statement

fixed links to new computing repos, adding gdpr statement

keeping this branch up with master, but retaining lvalert
and igwn-alert capability.

so production events show nearby production superevents, mdcs show
mdc, etc

* superevent neighbo"u"rs is now a dict, where the key is the
   superevent_id, and the value is the superevent packet, which
   includes:
   - basic info, a list of g-events, and the preferred_event_data key,
     which has basic info and extra_attributes. Does not include
     superevent info (to avoid recursive loops)
* Also increasing window time to +/- 100s

see: https://gracedb-dev1.ligo.org/api/events/G403673

This merges the xmpp+kafka overseer changes into the alert
contents branch.

 * suppress twistd userwarnings forever
 * add CWB uploader

* igwn-alert envvars not being propagated to django, and
* container settings now recognize multiple instances of lvalert
overseer

Generally less hacky. Segregates lv/igwn-alert overseer namespaces.
Should install cleaner, but it requires some changes to the AWS
deployment and secrets.