title: Apply new configuration to devstack from local.conf
body: <p>If I set a couple of settings in my local.conf file in the /devstack folder for example:</p>
  
  <pre><code>ADMIN_PASSWORD=supersecret  
  DATABASE_PASSWORD=iheartdatabases  
  RABBIT_PASSWORD=flopsymopsy  
  SERVICE_PASSWORD=iheartksl
  </code></pre>
  
  <p>and then run </p>
  
  <pre><code>./stack.sh
  </code></pre>
  
  <p>but then later want to append this file with some network configurations for example:</p>
  
  <pre><code>FLOATING_RANGE=192.168.1.224/27  
  FIXED_RANGE=10.11.12.0/24  
  FIXED_NETWORK_SIZE=256  
  FLAT_INTERFACE=eth0
  </code></pre>
  
  <p>will those new setting be applied to the cloud when I run <code>./unstack.sh</code> and then <code>./stack.sh</code>?</p>