doc: add changelogs for zlib

PR-URL: #11489
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Sam Roberts <vieuxtech@gmail.com>
Reviewed-By: Roman Reiss <me@silverwind.io>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Italo A. Casas <me@italoacasas.com>

doc/api/zlib.md

@@ -277,6 +277,10 @@ Compression strategy.
 ## Class Options
 <!-- YAML
 added: v0.11.1
+changes:
+  - version: v5.11.0
+    pr-url: https://github.com/nodejs/node/pull/6069
+    description: The `finishFlush` option is supported now.
 -->
 
 <!--type=misc-->
@@ -315,6 +319,17 @@ Compress data using deflate, and do not append a `zlib` header.
 ## Class: zlib.Gunzip
 <!-- YAML
 added: v0.5.8
+changes:
+  - version: v6.0.0
+    pr-url: https://github.com/nodejs/node/pull/5883
+    description: Trailing garbage at the end of the input stream will now
+                 result in an `error` event.
+  - version: v5.9.0
+    pr-url: https://github.com/nodejs/node/pull/5120
+    description: Multiple concatenated gzip file members are supported now.
+  - version: v5.0.0
+    pr-url: https://github.com/nodejs/node/pull/2595
+    description: A truncated input stream will now result in an `error` event.
 -->
 
 Decompress a gzip stream.
@@ -329,13 +344,24 @@ Compress data using gzip.
 ## Class: zlib.Inflate
 <!-- YAML
 added: v0.5.8
+changes:
+  - version: v5.0.0
+    pr-url: https://github.com/nodejs/node/pull/2595
+    description: A truncated input stream will now result in an `error` event.
 -->
 
 Decompress a deflate stream.
 
 ## Class: zlib.InflateRaw
 <!-- YAML
 added: v0.5.8
+changes:
+  - version: v6.8.0
+    pr-url: https://github.com/nodejs/node/pull/8512
+    description: Custom dictionaries are now supported by `InflateRaw`.
+  - version: v5.0.0
+    pr-url: https://github.com/nodejs/node/pull/2595
+    description: A truncated input stream will now result in an `error` event.
 -->
 
 Decompress a raw deflate stream.