[dev-context] CGModules update: Image downsampling version 1.002 published.

Peter Münster submitted an update to the Image downsampling package. Version number: 1.002 License type: GNU General Public License Wants to be in ConTeXt distribution: no Wants to be synced with CTAN: no Summary description: Downsample image-files on the fly with MKIV. Announcement text: ---------------------------------------------------------------------- Works with ConTeXt version 2019.02.14. ----------------------------------------------------------------------