The content in page "Creating RPM Packages"
has been subsumed under "Package Tutorial: GNU Hello"
in the Package Maintainer Docs.
Thus, the page is removed
and all references to it are pointed to the Packaging Tutorial.
"Creating RPM Packages" has one subpage,
which is moved to a top-level page.
In a separate commit for the Package Maintainer Docs,
the url of "Creating RPM Packages" will be listed as an alias
of the "Package Tutorial" so that external links will keep working.
