enhancement: in pytan.sessions.Session()
enhancement: in pytan.sessions.Session()

* move response_prunes in _get_response() to
self.BAD_RESPONSE_CMD_PRUNES
* renamed self.last to self.LAST_RESPONSE_INFO, add initial null
variable to Object level and doc
* renamed self.REQ_RESPONSE to self.LAST_REQUESTS_RESPONSE, add initial
null variable to Object level and doc
* add self.RECORD_ALL_REQUESTS to Object level and doc, controls
whether every Requests response object gets appended to
self.ALL_REQUESTS_RESPONSES, also add kwargs pass thru to init
* add self.ALL_REQUESTS_RESPONSES to Object level and doc
* rename self.request_body to self.LAST_XML_REQUEST_BODY, add initial
null variable to Object level and doc
* rename self.response_body to self.LAST_XML_RESPONSE_BODY, add initial
null variable to Object level and doc
* add initial null variables to Object level and doc for: server, port,
server_version

tanium/pytan,tanium/pytan,tanium/pytan,tanium/pytan