Add changelog entry for complex numbers

Author: ZedThree

Changelog

@@ -1,7 +1,8 @@
  version 1.7.0 (not yet released)
 ===============================
+ * add support for complex numbers via `auto_complex` keyword to `Dataset` (PR #1295)
  * fix for deprecated Cython `DEF` and `IF` statements using compatibility header
-   with shims for unavailable functionality
+   with shims for unavailable functionality (PR #1277)
 
  version 1.6.5 (tag v1.6.5rel)
 ===============================