Fix #1326 - spelling errors

examples/http-restful-server/main.c

@@ -25,7 +25,7 @@ static void fn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
     struct mg_tls_opts opts = {
         //.ca = "ca.pem",         // Uncomment to enable two-way SSL
         .cert = "server.pem",     // Certificate PEM file
-        .certkey = "server.pem",  // This pem conains both cert and key
+        .certkey = "server.pem",  // This pem contains both cert and key
     };
     mg_tls_init(c, &opts);
   } else if (ev == MG_EV_HTTP_MSG) {