Add dependencies section to EPEL Packaging Guidelines
    
    The implements the recently discussed refinements to dependencies.  In
    summary, EPEL packages can require packages from the Target Base or
    other EPEL packages.  They can additionally recommend packages from
    other RHEL channels.
    
    https://lists.fedoraproject.org/archives/list/epel-devel@lists.fedoraproject.org/thread/VAYJH5EFAIWHKUKA7LIMASBHYVSW75IW/