FeatureReq: assign `YAML::Emitter` to `YAML::Node` (multiline string to yaml-cpp node)

[shemeshg]

I'd like to be able to:

  YAML::Emitter out;
  out << YAML::Literal << val;            
  yamlContent[key] = out

See also: https://stackoverflow.com/questions/22231418/adding-multiline-string-to-a-yaml-cpp-node