message: contrib: Detailed reporting for http errors in github-merge
  Print detailed error, this makes it easier to diagnose github API issues.
diff: @@ -23,6 +23,7 @@ import sys
  import json
  import codecs
  from urllib.request import Request, urlopen
  +from urllib.error import HTTPError
  # External tools (can be overridden using environment)
  GIT = os.getenv('GIT','git')
  @@ -57,6 +58,11 @@ def retrieve_pr_info(repo,pull):
  reader = codecs.getreader('utf-8')
  obj = json.load(reader(result))
  return obj
  + except HTTPError as e:
  + error_message = e.read()
  + print('Warning: unable to retrieve pull information from github: %s' % e)
  + print('Detailed error: %s' % error_message)
  + return None
  except Exception as e:
  print('Warning: unable to retrieve pull information from github: %s' % e)
  return None
  