add Name func option

Signed-off-by: Vasiliy Tolstov <v.tolstov@unistack.org>

config/options.go

@@ -10,6 +10,7 @@ import (
 )
 
 type Options struct {
+	Name       string
 	AllowFail  bool
 	BeforeLoad []func(context.Context, Config) error
 	AfterLoad  []func(context.Context, Config) error
@@ -116,3 +117,10 @@ func StructTag(name string) Option {
 		o.StructTag = name
 	}
 }
+
+// Name sets the name
+func Name(n string) Option {
+	return func(o *Options) {
+		o.Name = n
+	}
+}