Added basicConfig to logging and separated the use of the libraries available for opening URLs to use either PyCurl or Urllib2 and not to load both.
1. default initialisation temporarily disabled and used RequestsClient.config directly instead.
2. Added exception handling for status code 401 authentication failure to ArangoDB
Merge branch 'master' of https://github.com/appscluster/arango-python

Conflicts:
	arango/clients/__init__.py