Adding upstream version 115.7.0esr.upstream/115.7.0esrupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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+# Want
+
+- [Crates.io](https://crates.io/crates/want)
+- [Docs](https://docs.rs/want)
+
+A `Future`s channel-like utility to signal when a value is wanted.
+
+Futures are supposed to be lazy, and only starting work if `Future::poll`
+is called. The same is true of `Stream`s, but when using a channel as
+a `Stream`, it can be hard to know if the receiver is ready for the next
+value.
+
+Put another way, given a `(tx, rx)` from `futures::sync::mpsc::channel()`,
+how can the sender (`tx`) know when the receiver (`rx`) actually wants more
+work to be produced? Just because there is room in the channel buffer
+doesn't mean the work would be used by the receiver.
+
+This is where something like `want` comes in. Added to a channel, you can
+make sure that the `tx` only creates the message and sends it when the `rx`
+has `poll()` for it, and the buffer was empty.
+
+## License
+
+`want` is provided under the MIT license. See [LICENSE](LICENSE).