Specify the log4j configuration file at startup

Summary:
Openfire 4.3 changes log4j configuration

References:

• GitHub issue gizmotronic/openfire#3
• https://issues.igniterealtime.org/browse/OF-1676

Reviewers: dereckson

Reviewed By: dereckson

Differential Revision: https://devcentral.nasqueron.org/D2175