IB: Fixing dereg_mr before ckpt bug

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2264 ba6dc0ae-232f-0410-883f-9ebac64fc565
1. Fix SLURM resources discover function
2. Fix remote launch script to support SLURMTMPDIR variable



git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2265 ba6dc0ae-232f-0410-883f-9ebac64fc565