readme.md

Commands:

1. cargo new project_name
2. cargo build
3. cargo run
4. cargo run --bin file_name
5. rustc ./src/split.rs && ./split
6. rustc --crate-type=lib --crate-name=rary ./src/rary.rs
7. ls lib*
8. rustc ./src/main.rs --extern rary=library.rlib --edition=2018 && ./main