Update Firestore changelog. (#313)

* changelog

* Add React Native fix.

* Revert "Add React Native fix."

This reverts commit f19e49e.

* Add version number, and FieldValue.delete() feature missed in the 0.1.2 notes.

Author: mikelehen

packages/firestore/CHANGELOG.md

@@ -1,6 +1,13 @@
 # Unreleased
 
+# v0.1.4
+- [changed] Network streams are automatically closed after 60 seconds of
+  idleness.
+- [changed] We no longer log 'RPC failed' messages for expected failures.
+
 # v0.1.2
+- [changed] We now support `FieldValue.delete()` sentinels in `set()` calls
+  with `{merge:true}`.
 - [fixed] Fixed validation of nested arrays to allow indirect nesting
 
 # v0.1.1