What parts of a Grails application need to be stored in source-control? Some obvious parts that are needed:

• grails-app directory
• test directory
• web-app directory

Now we reach questions like:

• If we use a Grails plug-in (like gldapo), do we need to check in that plugin?
• Do Grails plugins install in the Grails directory, or your project?

I'm not looking to start a religious war about .project, so please ignore that, but are there any "hidden" project files I need to worry about, along with the plugin issues?

Converted to a community wiki, as new versions of Grails have changed some of these solutions, especially as regards plugins.