Fix null exception on function $routeSegment.contains

This is the StackTrace:
```
TypeError: Cannot read property 'name' of null
    at Object.$routeSegment.contains (http://127.0.0.1:9000/bower_components/angular-route-segment/build/angular-route-segment.js:186:41)
    at Object.value (http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:8522:19)
    at extend.literal (http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:8573:41)
    at Object.Scope.$eval (http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:9953:28)
    at http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:14799:36
    at http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:4464:13
    at Object.Scope.$eval (http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:9953:28)
    at Object.Scope.$digest (http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:9809:23)
    at Object.Scope.$apply (http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:10039:24)
    at HTMLHtmlElement.<anonymous> (http://ajax.googleapis.com/ajax/libs/angularjs/1.2.0rc1/angular.js:7613:22) 
```
Regards