Consider switching to another DB connection pool library

[dryewo]

BoneCP is quite old. Should take a look modern implementations:

• https://github.com/brettwooldridge/HikariCP

[sebastianpoeplau]

We might want to consider conman, which builds on hikari-cp (a Clojure wrapper for HikariCP) and HugSQL. HugSQL is very similar to Yesql, which we're using at the moment, but claims to implement some improvements.