YANG ordering fails for nested choice and action

[olofhagsand]

Clixon orders instance nodes (XML/JSON) according to YANG, especially for "ordered-by system".
However there were instances where ordering did not work and unrecognized nodes appeared in front of all others.
For example, consider YANG:

choice a 
  case b{
    leaf c;
    choice d {
       leaf e;

Its ordering of an XML instance is "c e" whereas it would show as "e c" since "e" is unrecognized.
This example is "nested choice". Another case is "action".

[olofhagsand]

Fixed by a516ee1