Add pattern support to hbcairo
Fixes and suggestions by Viktor Szakats

- HB_ISBYREF() is not needed when you're calling hb_stor*() functions.
- Declare always CAIRO_IMAGE_SURFACE_CREATE_FOR_DATA and
CAIRO_IMAGE_SURFACE_CREATE.
- Update hbcairo.hbx and align case.
Fix hb_stord to hb_stornd
Fix cairo_pattern_get_surface
Merge pull request #2 from oscarhdezsz/dev/oscarhdezsz/hbcairo/pattern

Dev/oscarhdezsz/hbcairo/pattern