Improve documentation to reflect our preference of pull requests over mailing list postings

index.html

@@ -2073,8 +2073,15 @@ https://...</pre>
 
     <li>
         <p>
-        Propose your final <code>*.mk</code> file to the mailing list.
-        Don't forget to tell us
+        Issue a
+        <a href="https://help.github.com/articles/creating-a-pull-request">pull request</a>
+        to propose your final <code>*.mk</code> file to us.
+        If you have trouble with pull requests,
+        send your file to the mailing list instead.
+        </p>
+        <p>
+        Either way,
+        don't forget to tell us
         if there are some pieces in your <code>*.mk</code> file
         you feel unsure about.
         We'll then have a specific look at those parts,