OSI 3.8.0 Documentation changes

[asadekasam]

After splitting the C++ binding and the python packages into separate repostories, several gaps appear in documentation the documentation. The purpose of this issue is to collect these gaps to be addressed in 3.8.0 release candidate (in preparation)

[TimmRuppert]

I have drafted an idea how we could consolidate the whole "installation xyz on plattform abc" situation. Please have a quick look at #889, are you guys agreeing with this direction of change in the documentation?