Fix up changelog. (#761)

A bunch of the "Unreleased" changes have actually been released, so I broke them out
into the appropriate versions. Also added a changelog entry for the 0.4.1 patch release
to fix Node.JS support.

Author: mikelehen

packages/firestore/CHANGELOG.md

@@ -1,14 +1,19 @@
 # Unreleased
-- [changed] Merged the `includeQueryMetadataChanges` and 
-  `includeDocumentMetadataChanges` options passed to `Query.onSnapshot()` into 
+- [changed] Merged the `includeQueryMetadataChanges` and
+  `includeDocumentMetadataChanges` options passed to `Query.onSnapshot()` into
   a single `includeMetadataChanges` option.
 - [changed] `QuerySnapshot.docChanges()` is now a method that optionally takes
   an `includeMetadataChanges` option. By default, even when listening to a query
-  with `{ includeMetadataChanges:true }`, metadata-only document changes are 
-  suppressed in `docChanges()`. 
-- [fixed] Fixed a regression in the Firebase JS release 4.11.0 that could
-  cause get() requests made while offline to be delayed by up to 10
-  seconds (rather than returning from cache immediately).
+  with `{ includeMetadataChanges:true }`, metadata-only document changes are
+  suppressed in `docChanges()`.
+- [feature] Added new `{ mergeFields: (string|FieldPath)[] }` option to `set()`
+  which allows merging of a reduced subset of fields.
+
+# 0.4.1
+- [fixed] Fixed a regression in Firebase JS release 4.13.0 regarding the
+  loading of proto files, causing Node.JS support to break.
+
+# 0.4.0
 - [feature] Added a new `Timestamp` class to represent timestamp fields,
   currently supporting up to microsecond precision. It can be passed to API
   methods anywhere a JS Date object is currently accepted. To make
@@ -21,8 +26,11 @@
   Query.get() should fetch from server only, (by passing { source: 'server' }),
   cache only (by passing { source: 'cache' }), or attempt server and fall back
   to the cache (which was the only option previously, and is now the default).
-- [feature] Added new `{ mergeFields: (string|FieldPath)[] }` option to `set()` 
-  which allows merging of a reduced subset of fields.
+
+# 0.3.7
+- [fixed] Fixed a regression in the Firebase JS release 4.11.0 that could
+  cause get() requests made while offline to be delayed by up to 10
+  seconds (rather than returning from cache immediately).
 
 # 0.3.6
 - [fixed] Fixed a regression in the Firebase JS release 4.11.0 that could