#1295 A[I] fallback on A.nz[I], when A dense
#1295 Refactored Sparsity::sub to support index-1
#1295 Added Sparsity::sub(vector,Sparsity,...)
#1295 Refactored sort.
No temporary vectors unless invert_indices=true.
#1295 Refactored Sparsity::elem.
The old implementation expected input in row-major format, remainder from #554.
New implementation accept either, though support row-major should be be dropped
#1295 Column major indexing inside x_function_internal.hpp
#1295 Column major indexing inside get/setnonzeros
#1295 Removed row-major support in Sparsity::elem
#1295 Refactored Matrix::getSub single argument
#1295 Refactored Sparsity::sub, two arguments
#1295 Refactored Matrix::getSub/setSub(Sparsity)
#1295 Refactored Matrix::setSub
#1295 Added support for negative indices, index-1 in Sparsity::erase
#1295 Added support for negative indices, index-1 in Sparsity::enlarge
#1295 Removed incomplete overload of Matrix::setSub
#1295 Refactored MX::setSub
#1295 Refactored MX::getSub
#1295 Added missing bounds checking in MX::getNZ
#1295 Fixed bug in Slice::isScalar
#1295 Avoiding negative indices in setNZ