Add https://github.com/tczajka/bigint-benchmark-rs

Author: youknowone

README.md

@@ -3,3 +3,7 @@
 A drop-in replacement for rust [num-bigint](https://github.com/rust-num/num-bigint) based on [malachite](https://github.com/mhogrefe/malachite) `Natural`.
 
 This is not an official malachite project. Please directly use malachite unless you need num-bigint compatibility.
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+# Performance
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+See https://github.com/tczajka/bigint-benchmark-rs