Experiment with supporting hyper 1.x#416

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erickt wants to merge 2 commits intotheupdateframework:developfrom

Commits on Jul 30, 2018

Convert Client::_fetch_target's lookup fn into a method
erickt
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Commits on Aug 1, 2018

WIP: Migrate over to futures 0.1 and hyper 0.12
erickt
committed