Bump version to 2.0.0 and add changelog

CHANGELOG.md

@@ -0,0 +1,19 @@
+## 2.0.0
+
+- Replace hash with faster and better finalized hash.
+  This replaces the previous "fxhash" algorithm originating in Firefox
+  with a custom hasher designed and implemented by Orson Peters ([`@orlp`](https://github.com/orlp)).
+  It was measured to have slightly better performance for rustc, has better theoretical properties
+  and also includes a signficantly better string hasher.
+- Fix `no_std` builds
+
+## 1.2.0 (**YANKED**)
+
+**Note: This version has been yanked due to issues with the `no_std` feature!**
+
+- Add a `FxBuildHasher` unit struct
+- Improve documentation
+- Add seed API for supplying custom seeds other than 0
+- Add `FxRandomState` based on `rand` (behind the `rand` feature) for random seeds
+- Make many functions `const fn`
+- Implement `Clone` for `FxHasher` struct

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rustc-hash"
-version = "1.2.0"
+version = "2.0.0"
 authors = ["The Rust Project Developers"]
 description = "A speedy, non-cryptographic hashing algorithm used by rustc"
 license = "Apache-2.0/MIT"

README.md

@@ -38,5 +38,5 @@ The `std` feature is on by default to enable collections.
 It can be turned off in `Cargo.toml` like so:
 
 ```toml
-rustc-hash = { version = "1.2", default-features = false }
+rustc-hash = { version = "2.0", default-features = false }
 ```