#1 Http digest support

[Radek Dvořák]

Http digest authentication

This implementation is limited:
* Does work only with qop="auth".
* Does not check cnonce.
* Hash is hardcoded to md5.
* Does not implement opaque

Tested only on Apache 2.2.11.
It has not been tested with python <2.6 (although I tried to write it in compatible manner)

[Radek Dvořák]

Http digest authentication

[Mikko Pallari]

+1 for the patch

[Nobody/Anonymous]

I can say your patch works perfectly with python 2.6 also. Thanks for you effort, really helped!