Auto merge of #5858 - dekellum:git-check-logging-and-test, r=alexcrichton
Improve verbose console and log for finding git repo in package check
Third attempt to resolve #5823 by improving logging and tests. This exposes the issue to testing, via verbose console output and is dependent on alexcrichton/git2-rs#341 as just released in git2 0.7.5 crate. Thus tests *should* now pass on all platforms, incl. windows, but I also intend to bump the minimal git2 release dependency (in a subsequently added commit).
cc: @Eh2406 thanks for your fix and help!