Fix a bug that causes routes to be relative even when in pushState

Fix a bug that causes routes to be relative even when in pushState. Normal link interaction handles this because Durandal intercepts it, but if a user opens a link 'in a new tab' Durandal doesn't intercept it, and a relative link is opened, which fails.

With this change, `href`'s bound to the hash will still work correctly when middle-clicked. Navigation is not affected otherwise.