Upgraded xym to 0.4.2, with related changes in method calls.

- Legacy-Id: 13741

ietf/submit/checkers.py

@@ -157,7 +157,7 @@ class DraftYangChecker(object):
                 sys.stdout = saved_stdout
                 sys.stderr = saved_stderr
                 # signature change in xym:
-                model_list = extractor.get_extracted_models(False)
+                model_list = extractor.get_extracted_models(False, True)
             except Exception as exc:
                 msg = "Exception when running xym on %s: %s" % (name, exc)
                 log(msg)

requirements.txt

@@ -51,6 +51,6 @@ Trac>=1.0.10,<1.2
 Unidecode>=0.4.18
 #wsgiref>=0.1.2
 xml2rfc>=2.5.0,!=2.6.0
-xym==0.4
+xym==0.4.2
 #zxcvbn-python>=4.4.14		# Not needed until we do back-end password entropy validation