contint: localhost.mediawiki vhost on ci labs slave

Create a http://localhost.mediawiki:9414/ vhost on CI labs slave, will
let us write some integration tests there, for example for pywikibot.

/srv/localhost/mediawiki belong to group 'root' since there is no
'jenkins-deploy' group in labs.

Change-Id: If7f8b2777137cb2056caaf920ab2277ff3e65a30
Merge "contint: localhost.mediawiki vhost on ci labs slave" into production