add refactoring multiple directories.

[drewverlee]

Current i don't see any mention of a project wide way to refactor directories. This comes up often enough to be a pain point. Ideally you can use clj-refactor, which will cover both symbols and their namesapces at the same time. However clj-refactor often fails.

The way i have found to do this is

• find-named-dir
• enter dir you want to rename
• press "t" in this new buffer to mark all files
• dired-do-rename-regexp (%R)
• enter new name