Blender Git Loki

More change to the gesture manager.

After check this a little more I make some changes to the
API and now work on the following form:
WM_gesture_init(C, type);

while() {
/* handler event, etc */
/* if something change. */
if(need_update) {
/* update the gesture data and notify about it. */
WM_gesture_update(C, data);
WM_event_add_notifier (.. WM_NOTE_GESTURE_CHANGE ..);
}
}
WM_gesture_end(C, type);

Another of the change is that now the gesture data is a link list
in the window struct, so we can have multiples "gestures" (but
of different type) at the same time.

Also take care that the "gesture data" is reusable, that mean that
only alloc it 1 time and use in all the place, that is
why don't support multiple gesture of the same type, but of course
that can be change.