[QA] New deployment server on beta

[Antoine Musso]

Hello,

A few hours ago I have changed the deployment server on the beta cluster
to be deployment-mira.  It is based on Jessie (instead of Trusty).

That is the achievement of a lot of work with Elukey and Moritz.  We
caught lot of issues but it seems to be almost in good shape right now.

Some details are still being polished up, but the Jenkins job that
update the beta cluster are already running on deployment-mira.


The old master deployment-tin (Trusty) will be reimaged to Jessie
soonish.  Then I guess operations team will be able to switch the
production servers as well.

Ref: https://phabricator.wikimedia.org/T144578

-- 
Antoine "hashar" Musso