Minificpp 644 - C API: add support to register terminate handler (and fix build of examples)

[arpadboda]

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[phrocker]

LGTM, but needs to be rebased

[phrocker]

@arpadboda Sorry I just noticed build failures in linux and tried it on a VM and it failed too. Seems pretty easy. The issue is in CMAKE, previously some artifacts weren't included. You may not need minifi, but only core-minifi -- though I haven't dug too deeply into it.

[phrocker]

new travis failure appears to be unrelated to this commit, so will merge. thanks!