Add documentation for `quiet` flag

README.md

@@ -2192,6 +2192,11 @@ set :protection, :session => true
     <tt>app_file</tt> setting if not set.
   </dd>
 
+  <dt>quiet</dt>
+  <dd>
+    Disables logs generated by Sinatra's start and stop commands. `false` by default.
+  </dd>
+
   <dt>reload_templates</dt>
   <dd>
     Whether or not to reload templates between requests. Enabled in development
@@ -2839,7 +2844,7 @@ being [extending the main object](https://github.com/sinatra/sinatra/blob/ca0636
 Sinatra applications can be run directly:
 
 ```shell
-ruby myapp.rb [-h] [-x] [-e ENVIRONMENT] [-p PORT] [-o HOST] [-s HANDLER]
+ruby myapp.rb [-h] [-x] [-q] [-e ENVIRONMENT] [-p PORT] [-o HOST] [-s HANDLER]
 ```
 
 Options are:
@@ -2850,6 +2855,7 @@ Options are:
 -o # set the host (default is 0.0.0.0)
 -e # set the environment (default is development)
 -s # specify rack server/handler (default is thin)
+-q # turn on quiet mode for server (default is off)
 -x # turn on the mutex lock (default is off)
 ```