Switchyard exceptions are not logged to fuse.log in karaf

When exception is thrown in some service (cannot call other service or so), nothing is written to fuse.log, so it's hard to find the root cause of the problem.

Example - with http-binding quickstart, if service is called with 'wine', it returns the expected number, but if called with 'vineyard', the first service tries to call second service, exception is thrown and nothing written to the log.