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