Fix Boost (increase min ver, fix inc variable), Enable c++17

* Boost min ver 1.34 -> 1.58
* Boost_INCLUDE_DIR -> Boost_INCLUDE_DIRS (DIR is for internal usage)
* Switch to use C++17
1 job for !3 with work/usta_boostfix in 6 minutes and 51 seconds (queued for 43 minutes and 48 seconds)
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