update changelog

DOCS/CHANGELOG.md

@@ -2,5 +2,22 @@
 
 ## [0.23.0-wip] *unreleased*
 
+### Added
+- new features: `_maxest`, `_value_all`, `_value[8|16|32|64|128|256|512|1024]`.
+- new traits `DataValue[Copy]`, `DataType[Copy]`, `DataRaw[Copy]`.
+- new types: `DataValue*`, `DataType*`, `DataRaw*`, `NoData`.
+- new modules: `lang::{c}`.
+- new re-exports: `SystemAlloc`, `std::env::*`.
+- new optional dependencies: `itertools`.
+- add more methods to `Env`.
+
+### Changed
+- rename features:
+  - `_docs_max` to `_max`, `_docs_min` to `_docs`.
+- rename re-exports: `Layout` to `MemLayout`, `LayoutError` to `MemLayoutError`.
+
+### Fixed
+- enable nightly features depending on `alloc` and `std`.
+- feature-gate namespaced re-exported unsafe methods with `unsafe··`.
 
 [unreleased]: https://github.com/andamira/devela/compare/v0.23.0-wip...HEAD