The previous code would terminate the play immediatley if any hosts
in the environment did not have a journal directory. This change runs
the journalbeat install role selectively on hosts that have the journal
directory, and skips hosts that do not.
In addition a legacy task to stop the play after uninstallation is removed,
this functionality is currently broken.
Change-Id: I412e3594c4b2292caafafb580bb4ede9ccfd3944