(maint) have beaker tests use the host.hostname instead of host.name

-  when you want the current hostname use host.hostname, for some
   provisioners host.name is the name provided by the user but the
   current hostname is generated on the fly and thus different.
Merge pull request #915 from anodelman/beaker-1.5.x-hostname-mistmatch

(maint) have beaker tests use the host.hostname instead of host.name