Add conduit-zstd
Add conduit-zstd

This is my package and I can maintain it on both hackage and stackage

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