public static Collection<ResourceFile> findModuleRootDirectories(ResourceFile rootDir,
			Collection<ResourceFile> moduleRootDirs) {
		// look for any external GPL modules
		findModuleRootDirectoriesHelper(new ResourceFile(rootDir, "../GPL"), moduleRootDirs,
			MAX_MODULE_DEPTH);
		return findModuleRootDirectoriesHelper(rootDir, moduleRootDirs, MAX_MODULE_DEPTH);
	}
Searches the given root directory for module root directories.  Adds any discovered module
root directories to the given collection.

@param rootDir The directory to start looking for module root directories in.
@param moduleRootDirs A collection to add discovered module root directories to.
@return The given collection with any discovered modules added.
Ghidra/Framework/Utility/src/main/java/utility/module/ModuleUtilities.java