fix(autocomplete): firing a change event when onAutocomplete occurs
fix(autocomplete): firing a change event when onAutocomplete occurs

The point of the change is so that valdiation should fire when using
the keyboard to select an option from the dropdown.

Fixes #514

aurelia-ui-toolkits/aurelia-materialize-bridge,aurelia-ui-toolkits/aurelia-materialize-bridge,aurelia-ui-toolkits/aurelia-materialize-bridge