Added EvictingBlockingQueue implementation. Closes #3882

[noamgrinch]

Initial commit for an EvictingBlockingQueue. Please share your input.

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[noamgrinch]

@googlebot I signed it!

[noamgrinch]

Fixing concurrency bugs regarding Remove() and will update pull request.

[noamgrinch]

Done. Can you please review? Thanks!

[thhart]

Any chance to get this approved finally?