Changelog: import changelog for v 1.0.2
Changelog: import changelog for v 1.0.2

The changelog for v 1.0.2 only existed in the 1.0.2 tag.

Includes adding dates to undated release entries.

Ref:
* https://github.com/Yoast/whip/commit/ddd1e0e0cbc154d0c688ce79cbd59ebd990eb210
* https://github.com/Yoast/whip/commit/e9df81e3360c81e28a2cae4469ec6aa54f7fd434

Yoast/whip