This helps avoid build artifacts (namely, nroff and gzipped-nroff man
pages) owned by root.
The variables allow choosing which generator to use for the man page.
These will be hooked to configure in a following commit.
The python script mkdocdeps.py is used to import the list of man pages
from the sphinx configuration to make.
This will delete the (release only) target update-man-versions. This
will be replaced in a followup commit.
This is the output from sphinx-quickstart, massaged a bit, along with
our existing man pages converted to rst.
A skeleton notmuch-emacs manual is also included. It is not suitable
for end user use yet.