Fix wrong package install command for Lua library

Looks like the command for Scala was accidentally used instead.
The lua-resty-jwt lib doesn't use LuaRocks, so my suggested command just downloads and unzips the current source.

Author: twistedstream

html/index.html

@@ -818,7 +818,7 @@ <h3 class="panel-title">Lua (openresty)</h3>
             </div>
 
             <div class="panel-footer">
-              <code>sbt: "com.jason-goodwin" %% "authentikat-jwt" % "0.3.5" </code>
+              <code>curl https://codeload.github.com/SkyLothar/lua-resty-jwt/tar.gz/master | tar -xz</code>
             </div>
           </div>
         </div>