Entity field access condition 2281113b

Updated version of my previous patch;  I've changed branches due to some very bad problems with "git rebase".

I'm aware I have two commits that appear here.  That's the problem -- I can't get git to go lower without pulling in commits I don't own.  If you folks can tell me how to fix this, much thanks.

The patch creates the plugin and test for the issue.
Correct, the access handler itself is not a service, but it is referencable from one, namely the EntityManager (which is a service). So what you do is (in ::create). $container->get('entity.manager')->getAccessController('your-entity-type').