Create save-connection command

[Adam Connelly]

Create a save-connection command that will be used to save connection information under a user specified name. The command usage will be:

dbversion save-connection [options]

Where the options will be:

  * -c --connectionString
  * -d --dialect
  * -r --driver
  * -p --provider
  * -n --name
  * -t --template
  * -e --export
  * -i --import

The information will be stored using the settings service, and the create command will be updated to support a saved connection being specified. If the template option is used, the name of an existing connection should be specified to be used as a template, and only the name option will be mandatory.

If no options are specified, the list of saved connections should be output.