config/config.go
func (c *Config) Clone() *Config {
	cc := *c
	cc.Exts = make(map[string]interface{})
	for k, v := range c.Exts {
		cc.Exts[k] = v
	}
	cc.KindMap = make(map[string]MappedKind)
	for k, v := range c.KindMap {
		cc.KindMap[k] = v
	}
	return &cc
}
func (c *Config) Clone() *Config {
	cc := *c
	cc.Exts = make(map[string]interface{})
	for k, v := range c.Exts {
		cc.Exts[k] = v
	}
	cc.KindMap = make(map[string]MappedKind)
	for k, v := range c.KindMap {
		cc.KindMap[k] = v
	}
	return &cc
}
// Clone creates a copy of the configuration for use in a subdirectory.
// Note that the Exts map is copied, but its contents are not.
// Configurer.Configure should do this, if needed.