Update ruby193-rubygem-therubyracer to 0.12.0-1.el6

- Remove version check which relies on d8 (shk@redhat.com)
- Update to 0.12.0 (shk@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 rubygem-therubyracer, version 0.12.0-1.fc18