2 More Packaging Guideline Updates

[Toshio Kuratomi]

There's 2 more Guidelines that were approved in past meetings that have just
been written up.

= Directory ownership update =
https://fedorahosted.org/fpc/ticket/5
6 +1 votes , no 0 votes, and no -1 votes

This update makes it clearer that packages like gtk-doc do not need to be
required simply to own a directory and gives some examples of things that
are required for other reasons vs only directory ownership.

= Not using Sourcedir =
https://fedorahosted.org/fpc/ticket/12

We sent this one to FESCo for review after approving it.  They also approved
it so it's now written up.  It prohibits the use of $RPM_SOURCE_DIR or
%{_sourcedir} to install files.  Instead, %{SOURCEN} should always be used.

-Toshio