Change dependencies to strings to prevent minification failures

When I minified the code, the following error is thrown: `Uncaught Error: [$injector:unpr] Unknown provider: tProvider <- t <- ExpiredInterceptor <- $http <- $compile`

This is due to the minification process, which is ruining the dependency injection. (Some background on this error here: https://coderwall.com/p/eeqo7q/debugging-unknown-provider-error-in-angular)

This PR simply uses strings to prevent these errors, as recommended in the link above. I also made some spacing adjustments for legibility (which is why the diff looks like nearly the whole file was changed.)

Works great for me when minified with these changes.