Add EventManager Component

Completed the EventManager component for adding event handlers and behaviours to classes that are components configured in application configuration files.
Update Component Classes

Add the call to the attach() static method in the Event Manager to inject event handlers and behaviours that could be added at some point in the future.
Merge branch 'feature/event-manager' into develop
Create Addon Configuration

Create a configuration file for the language addon, and move the configuration from the old main application config file. Also map the message model namespace to the correct file.
Create Addon Configuration

Create a configuration file that will load each addon and merge it into the main application configuration.
Remove Translation Model

It isn't used, so there is no point keep it for now. It kind of drifts between application models and language addon models.
Create ExtraSecurity Addon
Merge branch 'feature/addons' into develop