BUG 2412 - Restconf migration - marking deprecated classes

* mark basic deprecated classes and functionality which has to
be overwirte by this commit chain.

New faster Infrastructure API works with NormizedNodeContext
and it provides read/write REST msg body (JSON & XML) direct
to NormalizedNodeContext. So we have to replace all places
where we use StructuredData, CompositeNode, NodeWrapper and
all relevant REST codecs (e.g. XmlToCompositeNodeProvider...)

Change-Id: I33ff24e5a8de2876dfdb6ea263fc9cb659fc3db8
Signed-off-by: Vaclav Demcak <vdemcak@cisco.com>