Add job that tests rally and tempest integration

Rally has `rally verify` command that simplify usage of tempest.
It includes installation, tempest.conf generation, execution of tempest,
parsing and storing result to db.
As well there are such things like show results in different formats and
compare results of 2 runs.

Currently this functionality is partialy tested by gate-rally-dsvm-cli
But this job is more like tempest functional testing that doesn't fit
to this case well. E.g. we can run different rally commands but can't see
output in the way that we won't + we don't have enough flexiblity.

New job will trigger bash script, that will run set of rally commands
and publish results. So output will look similar to our perormance jobs:

http://logs.openstack.org/56/132556/9/check/gate-rally-dsvm-rally/36aa202/

Change-Id: Ibe105c596fa305e7d8bcd2ba90e8b9ed303f9b40
Merge "Add job that tests rally and tempest integration"