Provide DLL(s) as release

[gentlecolts]

In light of the recent webp exploit and subsequent patch needs, people are distributing built dlls for patching. These dlls, however, do not come from official sources, which requires trusting the sender. It would be much safer for everyone if this repository instead provided its own release, as an official, more trustworthy source.

[ProbablePrime]

This is a good idea, we'll see what we can do.

[ProbablePrime]

https://github.com/Yellow-Dog-Man/FreeImage/releases/tag/3.18.0-ydm-0.1.4

Subsequent releases will have them too.