update changelog for 1.23.1

Author: etpinard

CHANGELOG.md

@@ -10,6 +10,17 @@ https://github.com/plotly/plotly.js/compare/vX.Y.Z...master
 where X.Y.Z is the semver of most recent plotly.js release.
 
 
+## [1.23.1] -- 2017-02-13
+
+### Fixed
+- Fix `relayout` for `scene.camera` values [#1364]
+- Fix scaling on axis corner drag interactions for `bar` traces [#1370]
+- Allow `bar` and `histogram` traces to coexist on same subplot [#1365]
+- Fix `bar` position computations when placeholder traces are present [#1310]
+- Fix auto-axis-type routine for data-less `candelestick`traces [#1359]
+- Bower installs now fetch un-minified `dist/plotly.js` bundle [#1373]
+
+
 ## [1.23.0] -- 2017-02-06
 
 ### Added