review fixes

Author: horpto

README.md

@@ -36,6 +36,8 @@ moq [flags] source-dir interface [interface2 [interface3 [...]]]
 		go pretty-printer: gofmt, goimports or noop (default gofmt)
 	-out string
 		output file (default stdout)
+	-out-dir string
+		output dir (exclusive with -out)
 	-pkg string
 		package name (default will infer)
 	-stub

main.go

@@ -93,7 +93,7 @@ func run(flags userFlags) error {
 
 	switch {
 	case flags.outDir != "" && flags.outFile != "":
-		return errors.New("use only one from -out and -out-dir arguments")
+		return errors.New("use only one  of the flags -out and -out-dir")
 	case flags.outDir != "":
 		return mockToDir(m, flags.outDir, args...)
 	case flags.outFile != "":