Remove .git directory/repository of juliadoc in make install
probably fix #5818
@parallel documentation in stdlib
Merge pull request #5820 from amitmurthy/amitm/atpdoc

`@parallel` documentation in stdlib
$(DESTDIR)$(prefix)/$(private_libdir) is redundant, should be $(DESTDIR)$(private_libdir)

I spent so much time introducing these Makefile variables, and yet I still have no idea how to use them
Update download links for win-extras

OpenSUSE's packaging moves quicker than ours!
Merge pull request #5717 from xhochy/no-.git-juliadoc

Remove .git directory/repository of juliadoc in make install
Revert "Update download links for win-extras"

This reverts commit af0675311655b8903ff5ecf7d12b184dec94766a.
Update download links for win-extras
Re-re-re update Rmath

Stop fighting me, git