Added a tutorial on implementing an LSM-Tree storage engine using Rust.

[schrodingercatss]

Added a tutorial on implementing an LSM storage engine using Rust.

Description

Motivation and Context

How Has This Been Tested?

Types of changes

• [ ] Content Update (change which fixes an issue or updates an already existing submission)
• [ ] New Article (change which adds functionality)
• [ ] Documentation change

Checklist:

• [ ] My code follows the code style of this project.
• [ ] I have updated the documentation accordingly.
• [ ] I have read the CONTRIBUTING document.
• [ ] I have made checks to ensure URLs and other resources are valid