Added targetExclude

[nedtwigg]

Fixes #153, #194, #324.

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[JLLeitschuh]

Want to add tests? Other than that, this LGTM!

[nedtwigg]

Tests is definitely the right answer, and TBF, I would ask for tests if this were from a non-maintainer. But I've got a pretty tight time budget for this project, and the code change is quite small, so I'm gonna merge as-is since we've got a pretty decent hunk of improvements sitting in the changelog.