Update readme.md

Release gas benchmark as extra file

Cleanup unused variables in test

Add SPDX ID

Make H(0, 0) = 0

Outsource zero hashes storage & access

Reduce gas cost by using less memory storage

Using bitshifts for divison by two

Update readme.md

Improve documentation

Allow updating existing leaves through proof bits

Revert "Remove bits in favor of index method"

Reproduce inability to update leaves

Update readme.md

Remove bits in favor of index method