Refactored configuration system

Ignore-this: 6d9eea12bd6054db4bdffbbd6d7492c6

darcs-hash:20091125193554-1e3d8-8d19ea89f672495208ba88791dea8e5113c78de2
Fixed MSRPStreamDidEnd being sent twice

Ignore-this: 86e213934bf2f5a3d00786711a50a6a3

darcs-hash:20091126124042-b22ec-37f0c0e825bdb659a3930ce1d7ba95f2bd215915