Use standardized top_k=5 for top 5 accuracy
Use standardized top_k=5 for top 5 accuracy

This was implemented upstream in
https://github.com/Lasagne/Lasagne/commit/a8b5b3aa0d2d379927c094b3f800a16c3e007810
Now that we're using Lasagne git, this should work.

jonhoo/periscope,jonhoo/periscope