Cherry-pick changelog for 1.2.1 from v1 branch

Author: kadamwhite

CHANGELOG.md

@@ -6,6 +6,13 @@
 - **BREAKING**: Autodiscovery now either succeeds or fails; a WPAPI instance configured with default routes will no longer be returned.
 
 
+
+## v1.2.1 _Colomb_
+
+- Fix issue where `li` was improperly declared as a dev-only dependency, props @el-lsan & @jerolan.
+
+
+
 ## v1.2.0 _Space Is Only Noise_
 
 - **BREAKING**: The minimum supported node version is now v8.