[bugfix] millisec file logging

This fix adds millisecond logging to adhearsion.log. e.g.:

    [2014-04-03 12:00:01.624] DEBUG Punchblock::Connection::Asterisk: Starting up...

_Back in c0400eb1, millisecond-level logging was added.  But while I believe the intention was to have this added to both default log appenders, it did not appear in adhearsion.log._