add SLURM backend (copied from arc0/trunk)

arc.spec.in

configure.ac

debian/nordugrid-arc1-arex.install

doc/tech_doc/a-rex/arex_tech_doc.lyx

doc/tech_doc/a-rex/arex_tech_doc.tex

src/services/a-rex/a-rex.xsd

src/services/a-rex/infoproviders/ARC0mod.pm

src/services/a-rex/infoproviders/CEinfo.pl.in

src/services/a-rex/infoproviders/Makefile.am

src/services/a-rex/infoproviders/README

src/services/a-rex/infoproviders/SLURM.pm

src/services/a-rex/lrms/Makefile.am

src/services/a-rex/lrms/cancel_common.sh

src/services/a-rex/lrms/slurm/Makefile.am

src/services/a-rex/lrms/slurm/cancel-SLURM-job.in

src/services/a-rex/lrms/slurm/configure-SLURM-env.sh

src/services/a-rex/lrms/slurm/scan-SLURM-job.in

src/services/a-rex/lrms/slurm/submit-SLURM-job.in