Adapted MSRPChat stream class to new Credentials class

darcs-hash:20090519132428-58103-06e19250bffe623e9ce6645021a9c03cdfaa3f83
Adapted logstate.py to new Credentials object

darcs-hash:20090519135523-58103-35c6519decaf253dfcb25f755a95cb0810f14e6e