Fix a recently implemented clippy lint

https://rust-lang.github.io/rust-clippy/master/index.html#single_component_path_imports
"Import with single component use path such as `use cratename;`
is not necessary, and thus should be removed."

examples/cli.rs

@@ -12,8 +12,6 @@
 
 #![warn(clippy::all)]
 
-use simple_logger;
-
 ///! A small command-line app to run the parser.
 /// Run with `cargo run --example cli`
 use std::fs;