teuthology: extend Hadoop task to support branches
teuthology: extend Hadoop task to support branches

Modify the Hadoop task to support branches
being specified for both the Apache and Inktank
Hadoop branches.

Signed-off-by: Joe Buck <a95e51950b61b017a762bcc8a962bac0b1a073a0@gmail.com>
Reviewd-by: Sam Lang <70ab3b98ad075c66e7d3501cb42b80a7e41da316@inktank.com>

dmick/teuthology,michaelsevilla/teuthology,caibo2014/teuthology,dmick/teuthology,ivotron/teuthology,robbat2/teuthology,yghannam/teuthology,zhouyuan/teuthology,dmick/teuthology,dreamhost/teuthology,t-miyamae/teuthology,SUSE/teuthology,yghannam/teuthology,zhouyuan/teuthology,ktdreyer/teuthology,ktdreyer/teuthology,tchaikov/teuthology,SUSE/teuthology,michaelsevilla/teuthology,ceph/teuthology,tchaikov/teuthology,SUSE/teuthology,ivotron/teuthology,robbat2/teuthology,caibo2014/teuthology,dreamhost/teuthology,t-miyamae/teuthology,ceph/teuthology