add mention of new doc

Author: tommaso-moro

README.md

@@ -140,7 +140,7 @@ When no toolsets are specified, [default toolsets](#default-toolset) are used.
 </tr>
 </table>
 
-See [Remote Server Documentation](docs/remote-server.md#insiders-mode) for more details and examples.
+See [Remote Server Documentation](docs/remote-server.md#insiders-mode) for more details and examples, and [Insiders Features](docs/insiders-features.md) for a full list of what's available.
 
 #### GitHub Enterprise