Add poller_t::wait

[cacharle]

Fix #679

[coveralls]

Pull Request Test Coverage Report for Build 22876090221

Details

• 5 of 5 (100.0%) changed or added relevant lines in 1 file are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.009%) to 87.896%

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Files with Coverage Reduction	New Missed Lines	%
zmq.hpp	1	85.55%

Totals
Change from base Build 22846621795:	0.009%
Covered Lines:	944
Relevant Lines:	1074

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💛 - Coveralls

[gummif]

Thanks