[Guidelines Change] Change to the Packaging Guidelines

[Tom Callaway]

A few minor changes to the Fedora Packaging Guidelines have been made:

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The Ruby Packaging guidelines were updated to reflect the fact that
rubygem packages must have a Requires: rubygems, because that package
(rubygems) owns the RubyGems? directory structure.

https://fedoraproject.org/wiki/Packaging:Ruby#RubyGems

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The systemd Scriptlets for Fedora 18+ have had their corresponding
scriptlet Requires adjusted from "systemd-units" to "systemd", since
"systemd-units" is provided by the "systemd" package in Fedora 18+.
There is still a separation in previous releases of Fedora (16/17), so
packagers can choose to continue using the old Requires (systemd-units)
if they are targeting multiple versions of Fedora with a single spec file.

https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Macroized_scriptlets_.28Fedora_18.2B.29

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This guideline change was approved by the Fedora Packaging
Committee (FPC).

Many thanks to Vit Ondruch, Lennart Poettering, and all of the members
of the FPC, for assisting in drafting, refining, and passing these
guidelines.

As a reminder: The Fedora Packaging Guidelines are living documents! If
you find something missing, incorrect, or in need of revision, you can
suggest a draft change. The procedure for this is documented here:
https://fedoraproject.org/wiki/Packaging/Committee#GuidelineChangeProcedure

Thanks,

~tom