YAML: Use C bindings if available

C bindings offer a considerable speed increase, so use them when
available (i.e. if libyaml is installed).

While at it, explicitly use safe dump for reference-enabled YAML.

Fixes: https://jira.opnfv.org/browse/FUEL-346

Signed-off-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
2 files changed