private void addToModuleTree(String path, ApplicationModule module) {
			if (module == null) {
				return;
			}
			if (path.endsWith(".class")) {
				classTree.addNode(path, module.getName());
			}
		}
Puts a directory in the jar for Ghidra Extensions. This may be empty (if
no extensions are installed) but should exist nonetheless.

@throws IOException if there's an error writing to the jar
Ghidra/Features/Base/src/main/java/ghidra/util/GhidraJarBuilder.java