message: docs: add changelog for 4.4.6
diff: +<a name="4.4.6"></a>
  +## [4.4.6](https://github.com/angular/angular/compare/4.4.5...4.4.6) (2017-10-18)
  +
  +
  +### Bug Fixes
  +
  +* **animations:** properly support boolean-based transitions and state changes ([#19672](https://github.com/angular/angular/issues/19672)) ([f983a6c](https://github.com/angular/angular/commit/f983a6c)), closes [#9396](https://github.com/angular/angular/issues/9396) [#12337](https://github.com/angular/angular/issues/12337)
  +* **common:** attempt to JSON.parse errors for JSON responses ([#19773](https://github.com/angular/angular/issues/19773)) ([269f5ac](https://github.com/angular/angular/commit/269f5ac))
  +* **router:** RouterLinkActive should update its state right after checking the children ([53a807a](https://github.com/angular/angular/commit/53a807a)), closes [#18983](https://github.com/angular/angular/issues/18983)
  +
  +
  +### Performance Improvements
  +
  +* **animations:** reduce size of bundle by removing AST classes ([#19673](https://github.com/angular/angular/issues/19673)) ([76d2496](https://github.com/angular/angular/commit/76d2496))
  +
  +
  +
  <a name="5.0.0-rc.2"></a>
  # [5.0.0-rc.2](https://github.com/angular/angular/compare/5.0.0-rc.1...5.0.0-rc.2) (2017-10-12)
  