#1295 Refactored XFunctionInternal::jac.
Removed FunctionInternal::assignIgnore workaround.
#1295 B in A.nz[i]=B is transposed if needed (MX)
#1295 Only vectors can be automatically transposed during assignment
#1295 Disallowed -1 indices in getNZ, setNZ
#176 Updated getNZ, setNZ signatures to support index-1
#1295 Renamed lingering getNZ_const => elem_const
#1295 Allowing negative indices, index-1 in getNZ, setNZ (Matrix)
#1295 Allowing negative indices, index-1 in getNZ, setNZ (MX)
#1295 Added hasNegative helper function.
*std::min_element(v.begin(), v.end())<0 not defined if v empty.
#176 Improved rosenbrock.m