Make index type of Triplet default to SparseMatrix::Index as suggested by Kolja Brix. Fixes Bug 665.
Make index type of Triplet default to SparseMatrix::Index as suggested by Kolja Brix. Fixes Bug 665.

--HG--
branch : 3.2

robustrobotics/eigen,robustrobotics/eigen,robustrobotics/eigen,robustrobotics/eigen