switched to go-mod, updated codegangsta/cli -> urfave/cli

vendor/github.com/codegangsta/cli/cli.go

@@ -1,21 +0,0 @@
-// Package cli provides a minimal framework for creating and organizing command line
-// Go applications. cli is designed to be easy to understand and write, the most simple
-// cli application can be written as follows:
-//   func main() {
-//     cli.NewApp().Run(os.Args)
-//   }
-//
-// Of course this application does not do much, so let's make this an actual application:
-//   func main() {
-//     app := cli.NewApp()
-//     app.Name = "greet"
-//     app.Usage = "say a greeting"
-//     app.Action = func(c *cli.Context) error {
-//       println("Greetings")
-//     }
-//
-//     app.Run(os.Args)
-//   }
-package cli
-
-//go:generate python ./generate-flag-types cli -i flag-types.json -o flag_generated.go