Description of problem:
When a user adds a cartridge from the command line that is database based, we output the username, password, port, and url that they can use to access that.  However, if you are developer doing this the first time you may not realize that you can also access these via environment variables.  We should include in the "success" output the exact environment variable names for each value (probably as a separate section).  

We could eventually add something to automatically fill these values in or prompt (You added mySQL to a Rails cart, do you wish to update database.yml to use these environment variables).  That would be a way to smooth a common problem on setup.  

Version-Release number of selected component (if applicable):
1

How reproducible:
Always (noticed during postgre demo)

Steps to Reproduce:
1. Using rhc, add a mysql or postgre cartridge to an application
  
Actual results:
See info about user/password/url

Expected results:
See the environment variable names these will be available under