doc/go1.14: mention net/http.Header.Values, net/textproto.MIMEHeader.Values

These methods are new in Go 1.14.

Updates #34799
Updates #36878

Change-Id: I063f5cb4638d7e0716e6ce2a8c3fffced51bbd34
Reviewed-on: https://go-review.googlesource.com/c/go/+/217129
Reviewed-by: Brad Fitzpatrick <[email protected]>

Author: ianlancetaylor

doc/go1.14.html

@@ -532,6 +532,17 @@ <h2 id="library">Core library</h2>
 
 </dl><!-- math/big -->
 
+<dl id="net/http"><dt><a href="/pkg/net/http/">net/http</a></dt>
+  <dd>
+    <p><!-- CL 200760 -->
+      The new <a href="/pkg/net/http/#Header"><code>Header</code></a>
+      method <a href="/pkg/net/http/#Header.Values"><code>Values</code></a>
+      can be used to fetch all values associated with a
+      canonicalized key.
+    </p>
+  </dd>
+</dl><!-- net/http -->
+
 <dl id="net/http/httptest"><dt><a href="/net/http/httptest/">net/http/httptest</a></dt>
   <dd>
     <p><!-- CL 201557 -->
@@ -543,6 +554,18 @@ <h2 id="library">Core library</h2>
   </dd>
 </dl><!-- net/http/httptest -->
 
+<dl id="net/textproto"><dt><a href="/pkg/net/textproto/">net/textproto</a></dt>
+  <dd>
+    <p><!-- CL 200760 -->
+      The
+      new <a href="/pkg/net/textproto/#MIMEHeader"><code>MIMEHeader</code></a>
+      method <a href="/pkg/net/textproto/#MIMEHeader.Values"><code>Values</code></a>
+      can be used to fetch all values associated with a canonicalized
+      key.
+    </p>
+  </dd>
+</dl><!-- net/textproto -->
+
 <dl id="plugin"><dt><a href="/pkg/plugin/">plugin</a></dt>
   <dd>
     <p><!-- CL 191617 -->