Added some comments clarifying functionality in the install task.
Added some comments clarifying functionality in the install task.

I also put in a couple TODO comments for things to look at later.

Signed-off-by: Andrew Schoen <1bb641dc23c3a93cce4eee683bcf4b2bea7903a3@redhat.com>

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