Update README.md

[ghost]

On the step 3 you should especify the full path of the ListenerAggregateInterface, like this:

use Zend\EventManager\ListenerAggregateInterface; class CompanyResource implements ListenerAggregateInterface

or this:

class CompanyResource implements \Zend\EventManager\ListenerAggregateInterface

[muriloacs]

That was really helpful! Thank you