Here is a patch to add epub support to doc-view, via the mutool command of the
mupdf library,I guess the patch needs no further explanation. I've read the info
about sending patches, however, I don't understand the section about the
changelog (it mentions that there is a changelog or something, but it doesn't
say where). Also, the info tells us to write the commit log entries, but it does
not say where to do this.Looking at the changelog files, I guess that info is
just really outdated (am I right?).Anyway, the patch is in the attachment. If
there is some part of the 'protocol' that I did not understand then please
inform me about it.

Thank you