Utilities/Sphinx: Add SPHINX_INFO option to build and install Info manual
This generates the manual in the Info format and installs it into
I have tested that it is created and installed correctly both with
cmake -DSPHINX_INFO=ON and
./configure --sphinx-info on Linux.
I have kept things in alphabetical order, this is why e.g.
--sphinx-info goes before
Here is the manual at the commit of this PR: cmake.info