PR54587: LDAP connections used for authn were not respecting 
LDAPConnectionPoolTimeout due to confusion over what "bound" means.

Added some LDAP trace at TRACE5 to track how LDAP connections are
reused and rebound.



git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1452551 13f79535-47bb-0310-9956-ffa450edef68