Model search, compare, make submissions downloadable

Hello!
My enthusiasm for brain-score is still alive after cosyne :)
I realized some add-ons to the website would be nice to have for the research community to work more efficiently and make more use of the evaluation data.

1. Adding a (potentially live) search option (looking like [this](https://uploads.sitepoint.com/wp-content/uploads/2017/06/1498834554Ajax-Live-Search.png)) that is also responsive to the comparison chart
2. Export function for the comparison chart
3. Make the model submission downloadable "as-is" in order to let others do evaluations on them

Start by reviewing the website code for the model listing, comparison chart, and submission handling; no files or tests are named in the issue. Break the request into search and chart filtering, chart export, and downloading submissions as-is, then define completion criteria for each before estimating the work.

Written by the indexing model from the issue text.