Remove scripts related to autotool

I would like to keep them for some more months, maybe even for the 3.0 release. People might migrate after we release 3.0, so it could still be useful to them.

Sure, you can merge it whenever you think is better. I don't mind.

dune-autogen doesnt make a lot of sense right now... The remove-autotools one should of course stay.

Added 24 commits:

• 13816cab...3f5aaa7c - 23 commits from branch master
• 4935e077 - [cleanup] remove dune-autogen related to Autotools

I adjusted the commit to only remove dune-autogen.

mentioned in commit df5433fd

Status changed to merged

Mentioned in commit df5433fd

mentioned in commit ad7dc864