cygport file and patches attached.

The build system has changed from autotools to meson.  The former is no longer 
supported.

I have disabled gobject introspection for reasons explained here:

   https://sourceware.org/pipermail/cygwin-apps/2020-May/040093.html

This represents no change, because Yaakov disabled it (for different reasons) 
several years ago.  I'm hoping to be able to re-enable it at some point.

I went to some trouble, with the help of Jon Turney, to make the html docs 
build, so I packaged them in a (new) libbabl-doc package.  Is there any reason 
not to do this?

Fedora packages the docs also, in babl-devel-docs.

Ken