asObservable leaks #115
Description
https://github.com/plumpstack/plump/pull/114 added a per-plump cache of read subjects, as the read subjects are a bit expensive to build, tear down, and end up duplicating a lot of effort. The subjects themselves are refcounted, so they don't leak heavily, but they do leak a little.
what should happen is that there should be a separate garbage collector process that runs on a setInterval that examines each and decides whether or not to delete it - how many observers does it have? when was it last touched? make an LRU cache that can conditionally delete basically.