Move javelin execution into a run_javelin()

Wraps execution of javelin in run_javelin() which takes care of
config initialization and determining whether or not javelin should
even be run.  This fixes a new bug where javelin resources are being
destroyed when RUN_JAVELIN=False.

Change-Id: Id5c1ee9553624c4a3e1ae2db667df1e6fce4fcaf