Cabal revisions of fgl-5.6.0.0

Hackage metadata revisions edit the .cabal file after upload; each diff below is one revision.

 name:          fgl version:       5.6.0.0+x-revision: 1 license:       BSD3 license-file:  LICENSE author:        Martin Erwig, Ivan Lazar Miljenovic     other-modules:         Paths_fgl -    build-depends:    base < 5+    build-depends:    base < 4.12                     , transformers                     , array