cake3 - introduced auth system

* very basic auth system (an authenticate object needed to check policy and groups)
* support for old md5 hashing password with migration to default cakephp 3 algorithm
Merge branch 'cake3' into cake3-auth

Conflicts:
	src/Template/Layout/default.ctp
add loginPolicy through BEditaAuthenticate class

add also update user data in BEditaAuthenticate class after login success/error
add super basic group authorize handler

to auth only users that belong to backend group
cake3 - introduced auth system

* very basic auth system (an authenticate object needed to check policy and groups)
* support for old md5 hashing password with migration to default cakephp 3 algorithm
add loginPolicy through BEditaAuthenticate class

add also update user data in BEditaAuthenticate class after login success/error
add super basic group authorize handler

to auth only users that belong to backend group
add smarty template
add comments
Merge remote-tracking branch 'origin/cake3-auth' into cake3-auth

Conflicts:
	src/Auth/BEditaAuthenticate.php
	src/Auth/GroupAuthorize.php
	src/Auth/Md5PasswordHasher.php
	src/Controller/AppController.php
	src/Controller/UsersController.php
	src/Template/Layout/default.ctp
Merge pull request #524 from batopa/cake3-auth

Cake3: basic auth system