update docs not to install mercurial and get eventlet from the repo but use source.tar.gz from download.ag-projects.com/EventletTwisted instead

darcs-hash:20090211091511-b2873-4635dc3d554eaa0941c3c2fccf3c5971db9194a1
Renamed darcs project to python-sipsimple

darcs-hash:20090211092118-58252-2b65edba569ca18c8bebae97f233733808d25123