Renamed workspace name from `io_bazel_rule_rust` to `rules_rust` (#500)

Generated by running
```bash
LANG=C sed -i '' -e 's/io_bazel_rules_rust/rules_rust/' $(find . -type f -not -path "./.git/*")
```

There's some small amount of sorting in here as well (based on the new name)

Closes https://github.com/bazelbuild/rules_rust/issues/499

Blocked by https://github.com/google/cargo-raze/pull/298 and https://github.com/google/cargo-raze/issues/304
diff --git a/WORKSPACE b/WORKSPACE
index fc72f88..92ffdee 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -1,18 +1,18 @@
-workspace(name = "io_bazel_rules_rust")
+workspace(name = "rules_rust")
 
-load("@io_bazel_rules_rust//rust:repositories.bzl", "rust_repositories")
+load("@rules_rust//rust:repositories.bzl", "rust_repositories")
 
 rust_repositories()
 
-load("@io_bazel_rules_rust//proto:repositories.bzl", "rust_proto_repositories")
+load("@rules_rust//proto:repositories.bzl", "rust_proto_repositories")
 
 rust_proto_repositories()
 
-load("@io_bazel_rules_rust//bindgen:repositories.bzl", "rust_bindgen_repositories")
+load("@rules_rust//bindgen:repositories.bzl", "rust_bindgen_repositories")
 
 rust_bindgen_repositories()
 
-load("@io_bazel_rules_rust//wasm_bindgen:repositories.bzl", "rust_wasm_bindgen_repositories")
+load("@rules_rust//wasm_bindgen:repositories.bzl", "rust_wasm_bindgen_repositories")
 
 rust_wasm_bindgen_repositories()