runCommand -package:wai-app-static -package:io-streams -package:pandoc-plot -package:shake-plus is:exact -package:libmpd -package:graphviz -package:mongoDB -package:hledger -package:cabal-install -package:process

Run a Command.
Either calls the given continuation, prints help text and calls exitSuccess, or prints an error and calls exitFailure. See runSubcommand for details on subcommand support.
Given a list of command/action pairs, prompt the user to choose a command using dmenu and return the corresponding action.