update changelog, add lazy= to parent_children()

CHANGELOG.md

@@ -33,6 +33,11 @@
 + Added `addattr()`, `PrefixIdentifier()`, `mod_floor()`, `mod_ceil()`
 + First version to have unit tests! (Coverage is not yet complete)
 
+## 0.3.8
+
+- Fixed return types for `.sqlalchemy` module.
+- `sqlalchemy.parent_children()` now takes a `lazy` parameter. Backported from 0.5.0.
+
 ## 0.3.7
 
 - Fixed a bug in `b64decode()` padding handling which made the function inconsistent and non injective. Now, leading `'A'` is NEVER stripped.