Adapted sip_message to new basic SIP objects

Ignore-this: 8689efade8051d7e8dcda26a81be13ea

darcs-hash:20090612143432-1e3d8-893fc16b353bafbf59ecf260300fd880db944e64
Added _dict_to_pjsip_param function to sipsimple/core.util.pxi

Ignore-this: ba06b1180f4a27dc5fe83da0b8430ba2

darcs-hash:20090616094430-1e3d8-f95516f90116c2854ba50ab39782bdba5d1674bd