Fix include patterns for version-ranges (#329)

* Fix include patterns for version-ranges

- Remove `ranges.png` because it does not exist.
- Add `LICENSE` because it needs to be distributed in the crate.
- Add `README.md` because the top-level `Cargo.toml` for the `pubgrub`
  crate includes it
- Change `src` to `src/**` to match the top-level `Cargo.toml` for the
  `pubgrub` crate, although this doesn’t currently seem to make a
  difference in practice.

* Add number-line-ranges.svg referenced from the readme

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Co-authored-by: konstin <[email protected]>

Author: musicinmybrain

version-ranges/Cargo.toml

@@ -6,7 +6,7 @@ edition = "2021"
 repository = "https://github.com/pubgrub-rs/pubgrub"
 license = "MPL-2.0"
 keywords = ["version", "pubgrub", "selector", "ranges"]
-include = ["ranges.png", "src"]
+include = ["LICENSE", "README.md", "number-line-ranges.svg", "src/**"]
 
 [dependencies]
 proptest = { version = "1.6.0", optional = true }