…r usage in all contraction based kernels so that n is along x dir and m is along y dir blocks

…kernels. --add launch config generator function to launch optimal grid size kernel for these pairwise dist kernels

…ed up over previous version. -- improve logic of the grid launch config generator for x-dir blocks

…ced val for pre-volta arch

… for subsequent gridStrideX variations. this overall improves perf of fusedL2NN to 1.85x over previous version. --Also remove checking keys only check values in fusedL2nn test case, as it may happen a row has multiple keys with same min val

…und in launchConfigGenerator. --Use constexpr in shmemSize.

…e sure next grid stride doesn't pollute shmem before completion of this calculation

…t iteration of grid stride

…m::device_buffer

…of hellinger formula

…pected to work on pdf

…nly 2021

…and reverting in post completion. also add unrolls to ldg arrays in contractions

…improvement for pairwise distance kernels and fusedL2NN kernel