Add 'make make_necessary_dirs' alias

This MR adds a new make_necessary_dirs Makefile target, which is an alias for _script_install. This small change will be extended in Move bin/install to support/make_necessary_dirs (!799 - merged) where bin/install is moved to support/make_necessary_dirs which more closely matches the Makefile target here.

It pairs up with Draft: Call `make make_necessary_dirs` instead (gitlab!162388 - closed) and will also help /bin/check is a very generic binary name (#603 - closed).