Emacs + Org-mode can sort of do this using org-babel. A lot of people use it for literate programming, or even just for documenting their own emacs configurati

Emacs + Org-mode can sort of do this using org-babel. A lot of people use it for literate programming, or even just for documenting their own emacs configuration. I'm not sure if there's already a plugin or script that can take a selection of files like you mentioned, but it shouldn't be hard to write one either.