Make sure we don't issue unexpected warnings

Numba sparse: handle dot product between matrices more granularly to reduce the number of of format conversions

* Add comment regarding meaning of '*' operator with sparse matrices

* Implement sparse dot product in numba

* Overload T attribute in numba sparse matrices

* Implement toarray

* Add tocsr

Co-authored-by: Jesse Grabowski <48652735+jessegrabowski@users.noreply.github.com>

Co-authored-by: Jesse Grabowski <48652735+jessegrabowski@users.noreply.github.com>

Co-authored-by: Adrian Seyboldt <aseyboldt@users.noreply.github.com>
Co-authored-by: Jesse Grabowski <48652735+jessegrabowski@users.noreply.github.com>

2304 -> 288

* Handle static shape
* Rename to more readable Op classes
* Simplify perform