Adding new dependencies for in-core

Hi,

I've had a quick look into https://github.com/pgjdbc/pgjdbc/issues/345
(Share parsed query texts across different connections) and it looks
like https://github.com/ben-manes/concurrentlinkedhashmap would be
useful to implement the cache.

We don't need all the stuff CLHM has, but I see no easy&scalable way
of doing concurrent map with eviction by mere java.util.concurrent
stuff.

Well, I can do lock splitting (i.e. use multiple small LRU caches
instead of a single big cache), however that looks like reinventing
the wheel.

Can you suggest what is the best way of adding CLHM dependency?
Should it be added in plain?
Should it be shaded? (i.e. renamed to org.postgresql.clhm...)

I'm more inclined to the "add regular dependency" approach.

I expect similar question might appear if we consider using netty for IO.

--
Regards,
Vladimir Sitnikov