Let the user choose whether to respect settings from ggb file

[sh-csg]

mod_geogebra always overrides the settings (e.g. showing the menu bar) done by the user in the ggb file with those from the course module settings. Especially as the form elements used for configuration are quite hidden, this confuses a lot of teachers.

I'd suggest to make overriding of the settings configurable - and to respect the settings done in the ggb file by default.