"UI" Paging in Profilepage - WIP

Implemented a paging on the profile page for issue https://github.com/NuGet/NuGetGallery/issues/144

Screenshot with "DefaultPackageListPageSize=3" 

![capture](https://cloud.githubusercontent.com/assets/756703/3304635/54d949aa-f64d-11e3-809f-25fd25b84292.PNG)

The bad part is that the UserController is still using the current "PackageService.FindPackagesByOwner" method - so on each page ALL packages of the user will be loaded from the database. To calculate the "TotalDownload" number the code iterates over all packages. If there would be a more clever way to get the "TotalDownload" number the paging could be implemented inside the PackageService as well.

This is one of the oldest open issue (or the oldest?) - so before I rewrite more I wanted to show my current implementation.