func (h *CfgHandler) Load() error {
	buf, err := readFile(h.filePath)
	if os.IsNotExist(err) {
		return nil
	} else if err != nil {
		return err
	}
	err = Unmarshal(buf, h.cfg, h.fileExt)
	if err != nil {
		return err
	}
	return nil
}
Load reads config values from the local config file
(using the file path linked to the handler) and stores
them into the linked instance of host CLI config struct.
package config
import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"os"
	"path/filepath"
	"github.com/pelletier/go-toml"
	"github.com/tidwall/sjson"
	"gopkg.in/yaml.v2"
)
type CfgHandler struct {
	cfg interface{}
	filePath string
	fileExt string
}
func NewHandler(path string, cfg interface{}) *CfgHandler {
	h := &CfgHandler{
		filePath: path,
		cfg:      cfg,
		fileExt:  filepath.Ext(path),
	}
	return h
}