[exception.handle] Handle all handleable exceptions

A well written, defensive application will handle all exceptions that are likely to occur during normal activity.  To someone watching the console, the sudden display of a stack trace should be a cause for concern rather than something to ignore because they have seen it so many times.  A well-polished application should have no exceptions visible in the logs or on the console unless something needs investigation.  See the section [app.logging] for more information.  Problems that caused Exceptions should be resolved or escalated where the exception is caught, or not caught at all.