Update `grunt-karma` dependency

At version 0.6.2, the `grunt-karma` module's peerDependencies conflict
with the other modules in use by this project. Update to the latest
version to enable successful module resolution and prevent npm errors at
installation time.
Fix application Router unit tests

The application Router expects the document body to contain a `<main>`
element. Without it, all instances create a Layout without an element,
resulting in an error when LayoutManager attempts to render.

Ensure that the necessary element is present in the document before each
Router unit test.
Merge pull request #28 from jugglinmike/fix-tests

Fix tests