OPENDJ-1205 (CR-4428) Remove network layer from External ChangeLog implementation

After OPENDJ-1206, I could remove all old External ChangeLog (or ECL for short) related classes. I could also remove annoyingly strange APIs from various places of replication code.



ECLUpdateMsg.java, ServerStartECLMsg.java, StartECLSessionMsg.java, ECLServerHandler.java, ECLServerWriter.java, ECLSearchOperation.java, ECLWorkflowElement.java, ExternalChangeLogTest.java: REMOVED
Also removed package src/server/org/opends/server/workflowelement/externalchangelog as part of these deletes.

replication*.properties:
Removed now unused SEVERE_ERR_RESYNC_REQUIRED_TOO_OLD_DOMAIN_IN_PROVIDED_COOKIE.

ReplicationMsg.java:
Deprecated old ECL message types.

ReplicationBroker.java, ReplicationServer.java:
Removed all ECL related code.

ReplicationServerDomain.java:
Removed the now unused otherHandlers field, stopServer(MessageHandler), registerHandler(MessageHandler), unRegisterHandler(MessageHandler), unregisterOtherHandler(), getOldestState() and getLatestDomainTrimDate()

ServerHandler.java
Reduced visibility has much as possible after removing ECLServerHandler.



MultimasterReplication.java:
Renamed getECLDisabledDomains() to , included "cn=changelog" by default + changed client code to not add it anymore.

LastCookieVirtualProvider.java:
Consequence of the change to MultimasterReplication.

ChangelogBackend.java:
Consequence of the change to MultimasterReplication.getECLDisabledDomains().
Removed SearchParams.requestType and replaced its usage with the new isCookieBasedSearch()



MultiDomainServerState.java, ServerState.java, ReplicationDomainDB.java, FileChangelogDB.java, JEChangelogDB.java:
Removed now unused methods / fields.
Made private methods / fields that are now only used inside their declaration classes.



ChangelogBackendTestCase.java, SynchronizationMsgTest.java, FileReplicaDBTest.java:
Updated or removed tests as a consequences of the whole change.