Send XMPP Message through Stanza

Previously, when it sends XMPP info-query message, it sends in the
form of string. Now, it sends in more structured way through XML
stanza.

 - Two fields are added. One is data and the other is type.
 - Data field is intended for previously "<body>" for
 - Type field is for message types such as "send_msg", "con_req",
   and "con_resp"
Merge pull request #3 from kyuhojeong/stanza-msg

Send XMPP Message through Stanza