Readme: faq entry about why lts is on older ghc
Readme: faq entry about why lts is on older ghc

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fpco/stackage,michalkonecny/stackage,mrkkrp/stackage,jonschoning/stackage,simonmichael/stackage,massysett/stackage,clinty/stackage,iand675/stackage,soenkehahn/stackage,Daniel-Diaz/stackage