[radudoros]

Added Caffeine cache as a replacement to our guava wrapped implementation.
Additionally added micrometer and configured sending measurements for tagged solr queries and cache stats.

Addresses also #157

[clarin-bot]

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[twagoo]

It looks good! I have no experience with Micrometer, but I saw in the documentation that it has a few annotations. I wonder about @Timed in particular, and whether it could be used to make the timing in the SolrDaoImpl and its children a bit more declarative and clean. If not, I think this is perfectly accessible.

[radudoros]

Thanks! I looked a bit at @Timed: it needs some TimedAspect thing with Spring AOP/AspectJ (which Spring Boot would wire for us, but we're on plain Spring), and since fireQuery is called internally it wouldn't be intercepted.

I wanted to manage this PR - I wanted to test the whole setup locally before, to see if the grafana and graphite pick everything correctly. I'll merge it after my checks I wanted to do.