You could do this by performing an Advanced Search on the parent Folder, and then adding all of the results to your bundle.
If you just want Components, and not sub-Folders, then you can filter these out using the Types Advanced Search option to just return Components.
The setting that you probably want are:
- Searching term: *
- Also search in sub-sections: Ticked
- Content type: Components
- Number of results: All
You may want to look at my blog post from earlier in the year about Publishing Tridion Folders - Only instead of publishing the results of the search, you will want to add them to you Bundle.