Some small additions to angular.d.ts and angular-route.d.ts

Added $setValidity() method to IFormController.
IWindowService, IBrowserService and IRouteParamsService now all have a '[key: string]:any' declaration, so that code like $window['someProperty'] is allowed to compile.
Thanks for adding the function, but the signature is wrong : https://github.com/angular/angular.js/blob/a990078173efd40a40e884af62a6f4b999fd0513/src/ng/directive/form.js#L126 

Looks like it should be more like what is already there for `INgModelController`