xml printer BUGFIX missing namespace for identityref/instance-identifier
xml printer BUGFIX missing namespace for identityref/instance-identifier

In case the leafref points to an instance-identifier or identityref,
the necessaru XML namespaces for the prefixes used in the value were
not defined (printed). Now, in case of leafref, the target data type
is resolved and the value is printed according to this type.

PavolVican/libyang,PavolVican/libyang,PavolVican/libyang,PavolVican/libyang,PavolVican/libyang