Removed redundant cdef's, fixed structures declarations.

FIXES:

* Removed redundant cdef's, as functions declared within "cdef extern" block receives this automatically.
* Fixed structures declarations, adding "pass" to them (this can be done only inside "cdef extern" blocks).

Signed-off-by: Bruno Abinader <bruno.abinader@indt.org.br>

git-svn-id: https://garage.maemo.org/svn/carman/branches/carman-0.7-beta2/python-purple@1271 596f6dd7-e928-0410-a184-9e12fd12cf7e