code: def GET_namespaces( self, path_info ):
          
          qs_values = path_info['qs_values']
          offset = qs_values.get('offset', None)
          count = qs_values.get('count', None)
  
          blockstackd_url = get_blockstackd_url()
          namespaces = blockstackd_client.get_all_namespaces(offset=offset, count=count, hostport=blockstackd_url)
          if json_is_error(namespaces):
              # error
              status_code = namespaces.get('http_status', 502)
              return self._reply_json({'error': namespaces['error']}, status_code=status_code)
  
          self._reply_json(namespaces)
          return
docs: Get the list of all namespaces
          Reply all existing namespaces
          Reply 502 if we can't reach the server for whatever reason