public List<PluginPackage> getPluginPackages() {
		List<PluginPackage> list = new ArrayList<>(descriptionsByPackage.keySet());
		Collections.sort(list);
		return list;
	}
Used to convert an old style tool XML file by mapping the given class names to plugin
packages and then adding <b>all</b> plugins in that package.  This has the effect of pulling
in more plugin classes than were originally specified in the tool xml.

@param classNames the list of classNames from the old XML file
@return the adjusted set of plugin class names
Ghidra/Framework/Project/src/main/java/ghidra/framework/plugintool/PluginsConfiguration.java