Bug 4560: Improve config system logging for debuggability

Bug 4560: Improve config system logging for debuggability

When a config push fails, most of the exceptions that are thrown are
unchecked (like IllegalArgumentEx) and they aren't explicitly caught
so they propagate to the top-level ConfigPersisterActivator thread and
got printed to syserr. So I added a catch and logged to error.

I also added context to the logged message which outputs the xml file
name to aid in debugging issues.

I also added info logging when a config push starts and when it
successfully completes to further aid in debugging issues.

Change-Id: I3db9dcad3cba0abd58c045bc1047e08d6f19ccd3
Signed-off-by: Tom Pantelis <tpanteli@brocade.com>