quartz_image_surface: add missing include for Cairo::QuartzImageSurface
quartz_surface test: add Cairo::QuartzImageSurface test
reduce cairo-quartz-image include scope.

Because cairo-quartz-image.h needs only rb_cairo_surface.c.
Merge pull request #27 from cosmo0920/add-quartz-image-include

Add missing cairo-quartz-image.h include

Patch by Hiroshi Hatake. Thanks!!!