* debian/control (libspot-dev): Do not depend on an exact version of
spot.
(spot-doc): depend on libjs-mathjax.
* debian/rules: Patch doc/userdoc/ to use the local version of MathJax.
* 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.
