Txaty Go Merkletree Versions Save

Minor fixes.

Performance optimization and readability enhancement.

This release includes various refactors:

1. Upgraded to Go 1.21, using the built-in min function;
2. Upgraded dependencies;
3. Upgraded GitHub Action pipelines, adding Codacy;
4. Remove the global worker pool and add the worker pool to the MerkleTree struct. So now, each MerkleTree uses its dedicated worker pool;
5. Change pool worker arguments to pointers to separate specific arguments, enhancing readability;
6. Fixed minor formatting issues and typos;
7. Added more comments;
8. Updated README.

1. Add DisableLeafHashing in Config, allowing users to use the byte values directly as the tree leaves without hashing procedures;
2. MerkleTree.GenerateProof() method is renamed to MerkleTree.Proof();
3. Refactor and bug fixes.

• If it is set to true, then the sibling hash pairs are first sorted in ascending order, and then concatenated.
• Otherwise, no change.

1. Use general arg struct and return type to improve goroutine pool performance,
2. Order fields in structs for memory saving,
3. Gool (goroutine pool) version upgrade.

1. In Config, there are three modes: ModeProofGen (default), ModeTreeBuild, ModeProofGenAndTreeBuild. ModeProofGen directly generates the proofs for all the blocks. ModeTreeBuild builds up and cache the Merkle Tree, this is useful when generating the proofs for only a few blocks.
2. Performance improvement via goroutine pool. I implement a simple goroutine pool: gool (github.com/txaty/gool). It significantly improves the parallel algorithms' performance.