Add the `proto-lens-protobuf-types` package.
Add the `proto-lens-protobuf-types` package.

It has been released on Hackage.  It will also eventually be a dependency
for the next release of the `tensorflow-proto` package.

Also remove old comments referencing a closed issue.

ethercrow/stackage,michalkonecny/stackage,alanz/stackage,athanclark/stackage,garetxe/stackage,jonschoning/stackage,phaazon/stackage,mrkkrp/stackage,GregorySchwartz/stackage,int-index/stackage,Daniel-Diaz/stackage,iand675/stackage,ygale/stackage,fimad/stackage,asr/stackage,k0ral/stackage,peti/stackage,mstksg/stackage,simonmichael/stackage,creichert/stackage,fpco/stackage,wereHamster/stackage,mgajda/stackage,stackbuilders/stackage,spencerjanssen/stackage,massysett/stackage,Shimuuar/stackage,soenkehahn/stackage,clinty/stackage,lwm/stackage