WFLY-2709 add missing resource key

The connector subsystem is missing the resource key
“connection-definitions.clear-statistics”. This results in a exception
when looking at the connection definitions of a resource adapter in
VisualVM.

 * add the resource key "connection-definitions.clear-statistics"

Issue: WFLY-2709
https://issues.jboss.org/browse/WFLY-2709
[WFLY-2498] Take the scheme into account when sending the redirect for logout.

i.e. preserve https.

Also eliminate the round trip to DomainApiHandler as that no longer needs to be cleared.
[WFLY-2609] Work around inconsistent deployment/subdeployment resource registrations for JPA