Added AppCentralHelper class
Added update action in application.php script for updating AppCentral applications list
Added comments
The AppCentral update button now updates the whole repositories and
applications list.
Updated change log
Added support for minimum version number check in findApplication
Added missing return false
Added appid in application versions list
Updated docs
Added method to find the latest version number from a version list
Added automatic resolution and installation of application dependencies from AppCentral