* pbs: new virtual package
Some of our clusters have an older installation of
libtorque and tm.h that are *not* from OpenPBS. Using the current
openpbs dependency for openmpi causes concretization errors due to
restrictions on older python and hwloc requirements that don't apply,
even with an external non-buildable installation.
The new 'torque' bundle package allows users to point to that external
installation without problems.
Detailed description of torque by Sergey Kosukhin <skosukhin@gmail.com>