Fixed is-composing payload definition to consider state element required

Ignore-this: d0f6e219ef2dc892dfeb2cc7b1a9de5

darcs-hash:20091229100640-1e3d8-1cbfa55d844605ca10a7da1068b6be658e6c1328
Fixed ChatStream to not assume all elements are present in is-composing

Ignore-this: d9d3d11bd435efa221c9a761a7bbb93d

darcs-hash:20091229100909-1e3d8-cafe3861b7a2ee3cbbadf321a7d76177a49f0528
Added conference XML application (RFC4575)

Ignore-this: 75fa809b3566e5a13bee3f8f2fc0ea83

darcs-hash:20091229110219-56b4d-6de0710115addcf9e91ddf28cc942eaa04acf3d2
Removed unused import from cipid application

Ignore-this: 1c9800eb507d4858284cc38f42ea9b44

darcs-hash:20091229110452-56b4d-adaecb0355a52e4dbd0e83d4f4998d762afaac75