Prepare changelog for v0.8.6

Author: richvdh

CHANGELOG.md

@@ -1,7 +1,14 @@
+Changes in [0.8.6](https://github.com/matrix-org/matrix-react-sdk/releases/tag/v0.8.6) (2017-02-04)
+===================================================================================================
+[Full Changelog](https://github.com/matrix-org/matrix-react-sdk/compare/v0.8.6-rc.3...v0.8.6)
+
+ * Update to matrix-js-sdk 0.7.5 (no changes from 0.7.5-rc.3)
+
 Changes in [0.8.6-rc.3](https://github.com/matrix-org/matrix-react-sdk/releases/tag/v0.8.6-rc.3) (2017-02-03)
 =============================================================================================================
 [Full Changelog](https://github.com/matrix-org/matrix-react-sdk/compare/v0.8.6-rc.2...v0.8.6-rc.3)
 
+ * Update to matrix-js-sdk 0.7.5-rc.3
  * Fix deviceverifybuttons
    [5fd7410](https://github.com/matrix-org/matrix-react-sdk/commit/827b5a6811ac6b9d1f9a3002a94f9f6ac3f1d49c)