Program built in Chapter 12 of *The Rust Programming Language* Book.

Consists of a `main.rs` file which runs the library code in `lib.rs`, where the bulk of the logic is kept for easier testing.  
Comes with a test file `poem.txt`.

Options to run:
- `cargo run search-term path-to-file`
- `cargo build --release` -> builds an executable in `target/release/` which can be run standalone