Cabal revisions of shakespeare-2.0.18

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

 name:            shakespeare version:         2.0.18+x-revision: 1 license:         MIT license-file:    LICENSE author:          Michael Snoyman <michael@snoyman.com>   ChangeLog.md  library+    build-depends: aeson <1.6+     build-depends:   base             >= 4.9     && < 5                    , time             >= 1                    , containers