KMultiPart implements "server push" for KHTML/Konqueror:
it handles the multipart/mixed and multipart/x-mixed-replace
mimetype, embedding the appropriate component (part).

Documentation at http://www.netscape.com/assist/net_sites/pushpull.html

Typical real-world uses: webchats, webcams...

Testcases:
  http://stein.cshl.org/WWW/software/CGI/examples/

TODO:
* Use the new streaming API of KParts to pipe data into the part,
the current code does that for KHTML only.
* Change KHTML so that it embeds KMultiPart for images which send multipart/x-mixed-replace
data.
