Initial example of Data names to suit better use of boost::variant.
adding method to provide the root_path in permanent_store / required by PmidNode
Adding Serialise and a constructor with serialises string to StructuredDataVersions::Version

Signed-off-by: moadeli <mmoadeli@maidsafe.net>
Merge remote-tracking branch 'origin/data_name_types' into next
Improved data type handling.
fixes minor typo.
Merge branch 'next' into sure_stuff