Per-group editable (selectable) policies for build trigging / dependency mgmgt

The groups and trigging of dependent modules are great (and necessary) features for large projects, but I am not so happy with all of the trigging/dependency mechanisms. I think a few different trigging and scm-relative policies should be available, and that these should be selectable in the group setup (radio buttons or something). These are separate jira issues.

We have tried continuum alpha-1 in a large organization building software that transfers large amounts of money. We use several groups, each with 15-30 modules, containing a few installable artifacts that must fit together. I have a number of suggestions on improvements that should give faster large-project builds and more precise control over the actual contents of modules with several in-house dependencies.