added support for multiple jdl ads

jess/api.py

@@ -97,9 +97,9 @@ class JDL(collections.OrderedDict):
                     else:
                         out.write('{} = {}\n'.format(k, ', '.join(v)))
                 if jdl_ads:
-                    out.write('\n'.join(jdl_ads.split('_NL_')))
+                    out.write('\n'.join(jdl_ads))
                     out.write('\n')
-                out.write('queue\n') 
+                out.write('queue\n')
                 return
             else:
                 raise jess.JessException("Serialization to unsupported backend {}".format(backend))