implement nushell completions (#24)

closes #19

Reviewed-on: http://192.168.1.227:3000/sfrembling/pallet/pulls/24
Co-authored-by: godsfryingpan <sfrembling@gmail.com>
Co-committed-by: godsfryingpan <sfrembling@gmail.com>

Cargo.toml

@@ -7,6 +7,7 @@ description = "A project manager and build system for C inspired by Rust's Cargo
 [dependencies]
 clap = { version = "4.6.0", features = ["derive"] }
 clap_complete = "4.6.0"
+clap_complete_nushell = "4.6.0"
 colored = "3.1.1"
 glob = "0.3.3"
 serde = { version = "1.0.228", features = ["derive"] }