logging: disable verbose dmurph

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>
util: fix StackOverflowError in DefaultSecurityApi

See details in https://issues.apache.org/jira/browse/SHIRO-510.

The workaround is to skip login if the login attempt is for the same principal
as the current authenticated user. Unclear if it's the right fix, waiting for
feedback on the ticket.

Signed-off-by: Pierre-Alexandre Meyer <pierre@mouraf.org>