Include new env vars in readme

README.md

@@ -398,6 +398,8 @@ There are a few optional environment variables available for customizing a Whoog
 | WHOOGLE_PROXY_PASS   | The password of the proxy server.                                                         |
 | WHOOGLE_PROXY_TYPE   | The type of the proxy server. Can be "socks5", "socks4", or "http".                       |
 | WHOOGLE_PROXY_LOC    | The location of the proxy server (host or ip).                                            |
+| WHOOGLE_USER_AGENT   | The desktop user agent to use. Defaults to a randomly generated one.                      |
+| WHOOGLE_USER_AGENT_MOBILE | The mobile user agent to use. Defaults to a randomly generated one.                  |
 | EXPOSE_PORT          | The port where Whoogle will be exposed.                                                   |
 | HTTPS_ONLY           | Enforce HTTPS. (See [here](https://github.com/benbusby/whoogle-search#https-enforcement)) |
 | WHOOGLE_ALT_TW       | The twitter.com alternative to use when site alternatives are enabled in the config. Set to "" to disable. |