Consider unique URL path per collection

[kerchner]

Now that we have disabled multi-select across data sets (ref #85), there may be an opportunity to refactor paths through the application so that the page after selecting a particular collection can also be accessed via a unique URL (e.g. /collection/:id).

This could be useful for providing links directly to a collection on TweetSets. For example, an Archivesspace record might opt to use a link like this, rather than a link to DOI in Dataverse, because TweetSets provides the user with additional functionality to filter the data set, etc. as compared to the static data files in Dataverse.