Add weak-cache

Description

Makes a weak-cache-factory available. Entries will be eagerly collected by the jvm, rather than only when there's memory pressure.
Implementation is fairly simple. I changed SoftCache to NonStrongCache and added an extra record parameter, which is the function
used to create the reference.
See https://github.com/pnf/core.cache/compare/clojure:master...master

Environment

None

Assignee

Sean Corfield

Reporter

import

Labels

None

Approval

None

Patch

Code and Test

Priority

Minor
Configure