Initial production release

I bet there's a lot of room for this script to grow and improve, but at this point, I feel confident that it works well enough to be considered ready for release.

I spent a lot of time covering edge cases, and I got everything that I could think of (note the emphasis) - duplicate file/dir names, capitalization issues, spacing issues... for my needs, this script works well, but I'm looking forward to seeing where it might go.