Route Errors (Y112)

https://github.com/johnpapa/angularjs-styleguide/edit/master/README.md
- Handle and log all routing errors using [`$routeChangeError`](https://docs.angularjs.org/api/ngRoute/service/$route#$routeChangeError).

_Why?_: Provides a consistent way to handle all routing errors.

_Why?_: Potentially provides a better user experience if a routing error occurs and you route them to a friendly screen with more details or recovery options.

``` javascript
/* recommended */
var handlingRouteChangeError = false;

function handleRoutingErrors() {
/**
* Route cancellation:
* On routing error, go to the dashboard.
* Provide an exit clause if it tries to do it twice.
*/
$rootScope.$on('$routeChangeError',
function(event, current, previous, rejection) {
if (handlingRouteChangeError) { return; }
handlingRouteChangeError = true;
var destination = (current && (current.title ||
current.name || current.loadedTemplateUrl)) ||
'unknown target';
var msg = 'Error routing to ' + destination + '. ' +
(rejection.msg || '');

/**
* Optionally log using a custom service or $log.
* (Don't forget to inject custom service)
*/
logger.warning(msg, [current]);

/**
* On routing error, go to another route/state.
*/
$location.path('/');

}
);
}
```