multiple file package changes in blender 2.7? In fact I want to pack many add-ons.

I was using some "standard" __init__.py check

but in reality this does not work, then I tried the example of wiki blender changing the deprecated import imp toof importlib import reload but this example does not work either!

I looked for some reference in manual but I do not get anything

also the CoDEManX code from link is not avalaible,... then ... 

what is the current way of packaging multiple files?
I made the example of wiki blender with a little change. It seems to work well.
Version 2.79

# To support reload properly, try to access a package var, 
# if it's there, reload everything
if "bpy" in locals():
    import importlib
    if 'simple_obj_import' in locals():
        importlib.reload(simple_obj_import)
    if 'simple_obj_export' in locals():
        importlib.reload(simple_obj_export)

import bpy
from bpy.props import *
#from io_utils import ExportHelper, ImportHelper
from bpy_extras.io_utils import ExportHelper, ImportHelper