Revert "multiple config"

common/cmdarg/cmdarg.go

@@ -1,16 +0,0 @@
-package cmdarg
-
-import "strings"
-
-// Arg is used by flag to accept multiple argument.
-type Arg []string
-
-func (c *Arg) String() string {
-	return strings.Join([]string(*c), " ")
-}
-
-// Set is the method flag package calls
-func (c *Arg) Set(value string) error {
-	*c = append(*c, value)
-	return nil
-}