reflect the fact that PETSc's MatGetOwnershipRange returns *one more*
than the global index of the last row. The hypre convention is to
return simply the index of the last row. CJR
is now stored as an SEQAIJ matrix and this broke some tests. The tests
were unnecessary, though, since we now no longer break PETSc's
encapsulation and instead use only the user interface.
