MAINT: update Changelog for release 2.3
## Version 2.3.0 (Unreleased)
+Includes many reworked examples in the example gallery.
+
### Enhancements
- Better errors for non-string column names, as well as automatic conversion
of ``pandas.RangeIndex`` columns to strings (#1107)
+- Renderers now have set_embed_options() method (#1203)
+
+- Added kaggle renderer & more HTML output options (#1123)
+
### Backward-incompatible changes
### Maintenance
+- fix typing requirement in Python 3.6+ (#1185)
+
+- Added support & CI testing for Python 3.7 (#1008)
+
### Bug fixes
+- Selection predicates now recognize all valid entries (#1143)
+- Python 2 support for `chart.save()` (#1134)
+
## Version 2.2.2 (Released August 17, 2018)
### Bug Fixes
