Provide headless Groovy-Eclipse feature

The current Groovy-Eclipse distribution provides features that can easily be installed into the Eclipse IDE, including all UI artifacts and patches for JDT. It cannot be installed into a headless Eclipse environment, e.g. for building Groovy projects with the Eclipse Buckminster project. It would be great if the Groovy-Eclipse project could provide such a feature. See the forum thread under http://www.eclipse.org/forums/index.php?t=msg&th=165908&start=0& for a motivation for this request.

I sketched a draft for this feature (see attached file). I could successfully install this feature into a regular Buckminster 3.6 headless environment and build a (simple) Groovy project without failure.

I also tried to run a script and a JUnit test from this headless environment. The former fails with the following message

Launch configuration type id "org.codehaus.groovy.eclipse.groovyScriptLaunchConfiguration" does not exist.

I suspect we need to include the plug-in that defines the launch configuration.

Running a unit test fails with

java.lang.IllegalArgumentException: No Code Select Helper found

Maybe this is also related to the missing Groovy launch configuration, but this message might just as well have other reasons. Does this error sound familiar to you, or should I better go looking in JDT code?