OPENDJ-2822 Enabling replication throws a NPE
OPENDJ-2821 status tool throws an exception with -X option

There was a host of small problems preventing dsreplication enable from working.

ConnectionWrapper.java:
In getSSLContext(), if trustManager is null then use the BlindTrustManager.

ServerDescriptor.java:
Fixed validation errors and ClassCastException.

HostPort.java:
Added static toString(String host, int port) to avoid validation.

ReplicationCliMain.java, ADSContext.java:
Code cleanups
Removed dead code.