Add an option to always send the client SSL certificate to LDAP server

This is the component issue for https://issues.jboss.org/browse/JBEAP-4439 and https://bugzilla.redhat.com/show_bug.cgi?id=1327758

The present code in LdapConnectionManagerService was designed so that the client cert is sent to authenticate the search account but during the username / password verification step, the client cert is not sent.

The present objective is to add an option (that will default to the old behavior) to send the client password also during the username / password verification.

This includes (citing dlofthouse):

• Implement management model based configuration and an implementation for the current version
• Port back to older versions using a system property.
• Forward port the system property to the current version for compatibility.