* minimum required php version is now 5.3.7.
* resources extensions is renamed to assets.
* getSubclasses added to Scabbia\Extensions.
* Extensions\Captcha\Captcha is moved to Extensions\Media\Captcha.
* Datasources extensions is improved.
* Database is updated due to Datasources changes.
* Cache::garbageCollect is moved to Io::garbageCollect.