* doc/org/index.org, doc/org/tut.org: New files.
* doc/Makefile.am: Add them.
* doc/org/setup.org: Adjust HOME link.
* doc/org/tools.org: Adjust UP link.
* debian/spot-doc.doc-base: The root is now index.html.
* debian/control: Update standars-version. Add missing ${misc:Depends}.
Use Depends: ${source:Version} for libspot-dev. Fix description of
spot.
* debian/spot-doc.doc-base: Move the doc to Science/Mathematics.