Adding basic history push state to the pager

[ericduran]

Basic fix for #17.

[ericduran]

@IgorMinar Thanks for the info.

I update the code to use $location. I also updated the lightbox project section to use $location since it was using history directly.

So now the pager and the projects should both be working correctly.

[ericduran]

I also just figured out how to listen for url changes. So this latest push makes sure the back button works with the pager.