bump copyright in src files to 2013
Rpm.hs: map ffi to libffi
move modules to Distribution/Rpm

Package/Rpm.hs -> Rpm/Build.hs
Package/Rpm/Main.hs -> Rpm/Main.hs
Package/Rpm/Setup.hs -> Rpm/Setup.hs
Package/Rpm/Utils.hs -> Rpm/SysCmd.hs
bump version to 0.9
split Rpm.hs into Build.hs and Spec.hs, move simplePackageDescription to new PackageUtils

- module renaming changes
- module splitting changes
- packageName and packageVersion also live in PackageUtils