Working on removing the dependency from Core in Utility
Adding a Readme and a composer.json for the Utility namespace
Removing the usage of Cake\Core\Exception in Security class

Replaced it with InvalidArgumentException
Removing the coupling between Security and Configure

Now the application will need to call Security::salt() directly
Add cakephp/utility to the replace list in composer.json
Merge pull request #4529 from cakephp/3.0-split-utility

3.0 split utility