Update ruby193-rubygem-rdoc to 3.12-12.el6

- Support non-SCL EL6 builds, install alongside ruby-rdoc (dcleal@redhat.com)
- rubygem-rdoc: remove debuginfo package (cduryee@redhat.com)
- remove empty tito.props and definition which are duplicate with default from
- with recent tito you do not need SCL meta package (msuchy@redhat.com)
Update rubygem-rdoc to 3.12-12.el6

- Support non-SCL EL6 builds, install alongside ruby-rdoc (dcleal@redhat.com)
- rubygem-rdoc: remove debuginfo package (cduryee@redhat.com)
- remove empty tito.props and definition which are duplicate with default from
- with recent tito you do not need SCL meta package (msuchy@redhat.com)
- new package built with tito
- Patch cross site scripting vulnerability CVE-2013-0256 (rhbz#908358).
- Provide the symlink in %{ruby_libdir}.
- Specfile cleanup.
- Removed BuildArch: noarch, as some files differ between arches.
- Add BR: rake to run all tests.
- Rebuilt for scl.
- Add missing obsolete (rhbz#809007).