Auto merge of #14592 - asajeffrey:util-goodbye, r=mbrubeck

Remove the util crate

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This PR removes the `util` crate.

* Replaced the `spawn_named` and `clamp` functions by appropriate uses of `std:🧵:Builder::spawn`, `std::cmp::min` and `std::cmp::max`.
* Moved `opts`, `prefs` and `resource_files` into a new `config` crate.
* Moved `remutex` and `geometry` into their own crates.

---
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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes do not require tests because they are refactorings

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components/bluetooth_traits/lib.rs

@@ -8,7 +8,7 @@ extern crate ipc_channel;
 extern crate regex;
 #[macro_use]
 extern crate serde_derive;
-extern crate util;
+extern crate servo_config;
 
 pub mod blocklist;
 pub mod scanfilter;