Updates for puller_simple to collect identity files from any of the known engines. Will prompt for password while we do not have an effective identity file to use.

git-svn-id: svn+ssh://civmxsrv2.duhs.duke.edu/Users/civmsvn/svn/repos/pipeline_utilities/trunk@2213 d41079a3-eaa1-4f09-8506-b324c47726bb
disabled fifo mode on cluster by checking that our hostname isnt civmcluster1. This needs improvement in the future. Especially looking into making fifos for the cluter and how that would be appropriate.

git-svn-id: svn+ssh://civmxsrv2.duhs.duke.edu/Users/civmsvn/svn/repos/pipeline_utilities/trunk@2214 d41079a3-eaa1-4f09-8506-b324c47726bb
Merge branch 'master' of github.com:jamesjcook/pipeline_utilities