all: Switch the --lang syntax to use argv instead

It was a bit awkward using `mgmt run lang --lang <input>` so instead, we
now drop the --lang, and read the positional argv for the input.

This also does the same for the --yaml frontend.

puppet/gapi.go

@@ -70,11 +70,6 @@ func (obj *GAPI) CliFlags(command string) []cli.Flag {
 		fallthrough
 	case gapi.CommandDeploy:
 		return []cli.Flag{
-			cli.StringFlag{
-				Name:  "puppet, p",
-				Value: "",
-				Usage: "load graph from puppet, optionally takes a manifest or path to manifest file",
-			},
 			cli.StringFlag{
 				Name:  "puppet-conf",
 				Value: "",
@@ -99,10 +94,13 @@ func (obj *GAPI) Cli(cliInfo *gapi.CliInfo) (*gapi.Deploy, error) {
 	//	 cliInfo.Logf(Name + ": "+format, v...)
 	//}
 
-	if !c.IsSet(Name) {
-		return nil, nil // we weren't activated!
+	if l := c.NArg(); l != 1 {
+		if l > 1 {
+			return nil, fmt.Errorf("input program must be a single arg")
+		}
+		return nil, fmt.Errorf("must specify input program")
 	}
-	s := c.String(Name)
+	s := c.Args().Get(0)
 	if s == "" {
 		return nil, fmt.Errorf("%s input is empty", Name)
 	}