exposed upload_only in peer_info

docs/manual.html

@@ -2524,6 +2524,7 @@ struct peer_info
                 seed = 0x400,
                 optimistic_unchoke = 0x800,
                 snubbed = 0x1000,
+                upload_only = 0x2000,
                 rc4_encrypted = 0x100000,
                 plaintext_encrypted = 0x200000
         };
@@ -2678,6 +2679,12 @@ the request timeout from when the request was sent.
 We're currently picking one block at a time from this
 peer.</td>
 </tr>
+<tr><td><tt class="docutils literal"><span class="pre">upload_only</span></tt></td>
+<td>This peer has either explicitly (with an extension)
+or implicitly (by becoming a seed) told us that it
+will not downloading anything more, regardless of
+which pieces we have.</td>
+</tr>
 </tbody>
 </table>
 <p><tt class="docutils literal"><span class="pre">source</span></tt> is a combination of flags describing from which sources this peer