Documentation task to describe by text and example if specific or generic devicemanager takes the related action.

It should be investigated if interfaces should be changed to reflect this function split.

e.g.: 

org.onap.ccsdk.features.sdnr.wt.devicemanager.onf.ne.ONFCoreNetworkElement12Basic.register()

and org.onap.ccsdk.features.sdnr.wt.devicemanager.impl.DeviceManagerNetconfConnectHandler.onEnterConnected()

need to clarify which events should be handled by base or by specific