message: chore(readme): remove strikethrough
  `<s>` in html is a strikethrough.
diff: #### Features
  * **client:**
  - * introduce PooledStream::<S>::get_ref ([a54ce30f](https://github.com/hyperium/hyper/commit/a54ce30f902772168bbd8dc90f26bb08cecde6ec))
  + * introduce `PooledStream::<S>::get_ref` ([a54ce30f](https://github.com/hyperium/hyper/commit/a54ce30f902772168bbd8dc90f26bb08cecde6ec))
  * introduce Response::get_ref ([5ef0ec2c](https://github.com/hyperium/hyper/commit/5ef0ec2cd2841e78508a61949a207187be914265))
  