core : Allow redirection of all logs using extension

A custom handler in a new module
org.ovirt.engine.core.logger handles all
logging using extensions.

Change-Id: Ia0dae8ffe53c3489af06d6684c72e6b431002404
Bug-Url: https://bugzilla.redhat.com/1078738
Signed-off-by: Ravi Nori <rnori@redhat.com>