Summary update

+ New system "updates" menu - update system and extensions
/ Update system of version control extensions - full done
* Fix displaying admin panel link in user iface - only admin/main
permission required
+ Add autoloader for system classes
* Improve extensions call function - front/back iface add and optimize
all other methods what work with call to backend
* Fix permissions in REST API
+ Add wordcount and character count in default WYSI editor
* Small fixes in com.user - icons of menu