I am new to Evernote and still learning the ropes. Can you make nested Notebook Stacks? Or does Evernote only go one stack deep? For example, I am working on a research project. I create a Notebook Stack called "Project A", but then I need 4 more Notebook Stacks under that, i.e.: Project AImagesPlanResearchArticlesWebsitesInterviewsPapersSupporting Docs Can I create a hierarchy like this? Or does tagging serve this function and everything just gets lumped under Project A with the tags Research, Plan, etc. Thank you!