Merge pull request #1179 from lucboudreau/master

[MONDRIAN-1844] Wraps initOlapServers into a callable that we run as the system user
[MONDRIAN-1844] Small change to Olap4jSystemListener. The callable must use the session in the holder, not the original one.
Merge branch 'master' of https://github.com/pentaho/pentaho-platform