added syntax for supporting ng-strict-di

[reppners]

Some small additions to enable usage of this component when running angular in strict-di mode.

Fixes this error: https://docs.angularjs.org/error/$injector/strictdi

Edit: Added missing di statement. Tested in own project where it works with ng-strict-di set.

[foolshat]

+1 Thanks reppners. I'm hitting this now after adding ng-strict-di Getting the following error Error: [$injector:strictdi] Lightbox is not using explicit annotation and cannot be invoked in strict mode

So would be great to merge reppners annotation changes. Thanks.

[compact]

Merged, thank you.