* glib/dbus-gvalue.c (marshal_variant): call _dbus_gvalue_marshal

* glib/dbus-gvalue.c (marshal_variant): call _dbus_gvalue_marshal
  instead of marshal basic so we can handle recursive types in a variant

* test/glib/test-dbus-glib.c: Add test for marshaling recurive types
  in variants

* test/glib/test-service-glib.c, test-service-glib.xml
  (my_object_echo_variant [EchoVariant],
  my_object_process_variant_of_array_of_ints123
  [ProcessVariantOfArrayOfInts123]):
  Add two test methods

* python/introspect_parser.py: New module for parsing introspect
  data.

* python/dbus_bindings.pyx:
  (various places): when throwing errors fix to use errormsg instead
  of message local variable because Pyrex can get confused with other
  message variables (initial patch by Robert McQueen
  <robert.mcqueen at collabora.co.uk>)
  (MessageIter::parse_signature_block): new method for getting the next
  block in a signiture.
  (MessageIter::append_strict): new method for appending values strictly
  using the passed in signature instead of guessing at the type
  (MessageItter:: append_dict, append_struct, append_array): use
  signatures to marshal children if the signature is available

* python/exceptions.py (IntrospectionParserException): new exception

* python/proxies.py (ProxyMethod::__call__): Marshal args with
  introspected signatures if available, else we fall back to the
  old way of doing things.
  (ProxyObject::_introspect_reply_handler ): parse introspection data

* python/service.py (ObjectType::_reflect_on_method): Properly
  terminate <method> if there are no args in the reflection data

* test/python/test-client.py: add tests for talking with the GLib
  test server.  This gives us better coverage for introspection since
  python to python will always generate arguments as variants.  It also
  allows us to test the robustness of the GLib bindings and interlanguage
  communications.