Add png resizer

Adds PNG resizer back into frontend.

This is so we can reduce the footprint of cutouts on the fronts.

CC @phamann @gklopper @rich-nguyen Could you guys look over this and make sure it's sensible please? Thank you!
@robertberry @gklopper I forgot to mention previously. Is there any chance we can change the url pattern so that the options are segments rather than query params. i.e. `/foo/bar/w124/h450/q70` rather than `/foo/bar?width=140&height=450` so that they match our current image paths and will make switching services easier in the future.