Add first-class support for binary crates

[mre]

This is a rebase of the work of @boringcactus in #736 onto the current master. Did this to make merging easier as a rebase was requested on the original PR.

@daxpedda fyi

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• [X] You have the latest version of rustfmt installed

$ rustup component add rustfmt

• [X] You ran cargo fmt on the code base before submitting
• [X] You reference which issue is being closed in the PR text

[jkelleyrtp]

Anything else we (the community) can do to help get this merged? It's a great feature that we've wanted/needed for a while.

[mre]

Fixed two merge conflicts. Any chance we can merge this soon?

[wooden-worm]

Is there anyone reviewing and merging PRs? I need this feature, such a shame this has been languishing for years.