Add database connection helper command

[humanmade]

Add database connection helper command

[roborourke]

This one is a bit meatier but will be helpful. A few more notes to assist in development:

• See the composer server logs command for a reference on how to check for subcommands and arguments
• Example .spf template: https://github.com/Chassis/SequelPro/blob/master/template.spf
• Get the mapped db ports using

  docker ps --format "{{.Ports}}" --filter name=altis-dev_db_1
  # -> 33060/tcp, 0.0.0.0:32123->3306/tcp
  

  0.0.0.0 is the host and 32123 in this case is the port on the host you can access it at
• username and pass is wordpress, wordpress

[roborourke]

Closed by #122