remove the static graph generation.

[kohlhase]

With the new TGView in place (see #261) , we should remove the old server-side graph functionality from the build system (do not generate the SVG graphs) and from the MathHub front-end (that is probably most in #261).

[kohlhase]

the most prominent instance of the graphs is in the glossary, where the "Concept Graph" functionality does not work any more. This is problematic for demos for me.

The URL we should use here is the SMGloM module graph (see UniFormal/TGView#24) for the respective archive, i.e. something like https://mmt.mathhub.info/graphs/tgview.html?type=archivegraph&graphdata=smglom/arithmetics just with a type=smglom or so.

We should change this in
./src/planetary-mmt/src/info/kwarc/mmt/planetary/GlossaryGenerator.scala:220:

and run this again to get a new glossary on MathHub.

cc: @Jazzpirate

[kohlhase]

This should also highlight the current smglom module (see UniFormal/TGView#25)