This is unfortunately a giant change, as all of the functionality that
is encompassed into module-sets currently had to migrate over to
multiple separate classes, including the new ksb::ModuleSet class and
subclasses.

This was a long-overdue change, however, and should allow for accurately
tracking a source module-set for a given module.

On the other hand this migration of logic has made it easier to
understand each of the individual pieces where they stand (e.g. there is
no longer a separate expandXMLModules and expandModuleSets).

In addition we can properly handle ignore-modules with wildcards just as
we do with use-modules (they even use the same matching logic) which
means that it is safe to integrate this into master (assuming no extra
boogs get added, of course).

This will also help with fixing some of the extant module-selection bugs
(321883, 299415).

BUG:321275
CCBUG:321667