QPID-5429: [Java Broker] Exceptions causing startup failure now written to qpid.log too

Previously, such exceptions were only written to stderr. This change means that they written to qpid.log too,
allowing configuration problems etc to be understood by refering to the one file.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1557052 13f79535-47bb-0310-9956-ffa450edef68