[Copyright] Fix copyright headers

Signed-off-by: Ludovic Ferrandis <ludovic.ferrandis@intel.com>
[Doc] add with-ua-prefix doc to README

Add missing with-ua-prefix option doc to the README.
Fix issue https://github.com/01org/dleyna-server/issues/37

Signed-off-by: Christophe Guiraud <christophe.guiraud@intel.com>