Add usage analytics to site

[cflann]

Wanted to open this up to the team.

I think it would be useful (and perhaps validating) to get an idea of how much usage the RCR is getting. On a general level this would be nice, but we could get more specific insights if desired (which resources are requested the most, that sort of stuff...). I'm guessing this could help out with grant stuff as well but that's not my area of expertise.

I'm sure people have privacy/ethics concerns here, so we could avoid Google Analytics or other problematic options. Doing a quick search, I came across Plausible analytics, which seems promising (open source). It's cheap for their hosted option, but can also be self-hosted using Docker. I'm not too familiar with our hosting process, but I think Heroku and Docker can play nice.

[kentpmckinney]

Heroku probably has some basic metrics built in, and if not, there are probably a lot of add-ons:

https://devcenter.heroku.com/categories/monitoring-metrics

We would need to run this by Street Roots for sure, as they likely need to comply with policies/regulations that touch on this. It might be something to bring up the next time we meet with them. It might be a possible feature that could include a report on the Admin page that shows the statistics.