Make InfoRoute return a long-valued date & the base repository URL.

We need `gitDate` as a long in order to make parsing easy when we deserialize back into `GitVersion`.

There was also some confusion in the controller over `githubUrl` - it was being treated as `gitRepoUrl` when being parsed, but the value being returned from `InfoRoute` was `gitCommitUrl`. I've updated it to return both, with names to match their source.