Re-add lost fix for DCDataSet zero reads
Merge pull request #86 from ComputationalRadiationPhysics/fix-lost-dcdataset

Re-add lost fix for DCDataSet zero reads
Add new parallel test for zero accesses

 - tests reading/writing with size=0
Add debug output
Remove working tests
Only print on error
More verbose output
Add MPI Barrier
Set debugging and SPLASH_VERBOSE
Print log to stdout
Add env var
Merge branch 'zero-access-dbg' of github.com:ComputationalRadiationPhysics/libSplash into zero-access-dbg