anchor.diff:  Common reasons deploying an app fails include:
   
   * You did not successfully create and bind a needed service instance to the app,
  -such as a PostgreSQL or MongoDB service instance.
  +such as a PostgreSQL service instance.
   Refer to Step 2: Create and Bind a Service Instance for a Ruby Application.
   * You did not successfully create a unique URL for the app.
   Refer to the troubleshooting tip <strong>App Requires Unique URL</strong>.
  
positive.code: cleardb          spark, boost, amp, shock      Highly available MySQL for your Apps
  ...
  elephantsql      turtle, panda, hippo, elephant   PostgreSQL as a Service
  ...
  mongolab         sandbox       Fully-managed MongoDB-as-a-Service
  ...
  </pre>
  
  
negative.code: that are available to you.
  
  The example shows three of the available managed database-as-a-service providers
  and the plans that they offer: `cleardb` MySQL and `elephantsql` PostgreSQL as a
  Service.
  
  <pre class="terminal">
  $  cf marketplace
  