Added configuration of Authentication Adapters to config and ChainFactory

Hi Evan,

my plan is to implement a module for a "Remember Me" Option on Login. My current idea is to just implement a Cookie Authentification Adapter and put that in the auth chain. That is why I created this Pull Request. From the architecture it seems that it was your intention to make it possible to have multiple adapters from the start.

Now I have a question about the next steps. In order to make this work the LoginAction would need to try and authenticate even if the request is not POST (because the cookie might be present none the less). 

One possible approach I can think of would be refactoring the loginAction a little bit in order to run the authenticate action no matter what. Another way could be to configure options to check the request against. A third option would be to add a new route checking for POST and handling the form submission differently. Any suggestions or thoughts how to handle that?