title: Which Exceptions get thrown from watson-developer-cloud pip module
body: <p>I started to migrate my Django apps to use the watson-developer-cloud module, and whilst running my unit tests noted that the service threw an exception under certain conditions. The exception turned out to be a WatsonException, which I now code for, but was wondering if that is the only exception that would be thrown. Currently my code looks like:</p>
  
  <pre><code>from watson_developer_cloud import LanguageTranslationV2 as LanguageTranslation
  from watson_developer_cloud import WatsonException 
  ...
  try:
    language_translation = LanguageTranslation(username='xxxx',
                                               password='yyy')
  
    languages_detected =  language_translation.identify(data)                                                ...   
  
  except WatsonException as err:
    ...      
  </code></pre>
  
  <p>My question is, is this sufficient to cover all error conditions?</p>