Create CHANGES.md

Author: achamayou

CHANGES.md

@@ -1,9 +1,11 @@
 ## Changelog
 
+### 1.46 (2017-06-13)
+  * Feature: #374 Shard BSONStore on `_id` rather than `symbol`
+
 ### 1.45 (2017-06-09)
   * BugFix: Rollback #363, which can cause ordering issues on append
 
-
 ### 1.44 (2017-06-08)
   * Feature: #364 Expose compressHC from internal arctic LZ4 and remove external LZ4 dependency
   * Feature: #363 Appending older data (compare to what's exist in library) will raise. Use `concat=True` to append only the