[OPENDJ-1478] CR-5392 Make it easier to add compatibility options to schemas

Creates a generic Option class and a SchemaOptions class to manage schema compatibility options.

git-svn-id: https://svn.forgerock.org/opendj/trunk/opendj@11335 41b1ffd8-f28e-4786-ab96-9950f0a78031
OPENDJ-1545 Remove Workflow, NetworkGroups and related attempts at building a proxy

Removed org.opends.server.api.Extension.
We are fully open source we do not need to support closed source extensions.


config.ldif:
Removed dn: cn=Extensions,cn=config.

ExtensionConfiguration.xml, Extension.java, ExtensionConfigManager.java: REMOVED

RootConfiguration.xml, RootCfgDefn.properties:
Removed the reference to extension.

DirectoryServer.java
Removed all references to Extension and ExtensionConfigManager.

git-svn-id: https://svn.forgerock.org/opendj/trunk/opendj@11339 41b1ffd8-f28e-4786-ab96-9950f0a78031