in a multi-module build, Continuum should tell SCM to exclude submodules to reduce the amount of unnecessary updates

say we check out Maven Plugins, and use the multi-module feature, and the parent is built with -N.

We can't pass -N to the checkout, as there might be something under src/ in the parent. But we don't need every plugin's module as they'll be checked out separately.

It would be good to be able to exclude all the submodules.