update frontend dependencies
update frontend dependencies

Mostly minor and patch releases. Grunt had a [major
release](http://gruntjs.com/blog/2016-04-04-grunt-1.0.0-released), but
it should not affect us.

Things that were not updated:

-   [protractor](https://github.com/angular/protractor/blob/master/CHANGELOG.md)
-   [angular-cache](https://github.com/jmdobry/angular-cache/blob/master/CHANGELOG.md)
    (see [issue](https://github.com/jmdobry/angular-cache/issues/234))
-   [typescript](https://blogs.msdn.microsoft.com/typescript/2016/07/11/announcing-typescript-2-0-beta/)
    announced version 2.0-beta some time ago, but the stable version has
    not yet been released.

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