message: Add note about HTML reports to changelog.
diff: @@ -14,6 +14,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
  - Criterion.rs can now report the throughput of the benchmarked code in units of
  bytes or elements per second. See the `Benchmark.throughput` and
  `ParameterizedBenchmark.throughput` functions for further details.
  +- Criterion.rs now generates a basic HTML report for each benchmark.
  ### Changed
  - The builder methods on the Criterion struct now take and return self by value
  