tool: Only depend on simple logger / clap for the binary release
as per the cargo reference for targets, we can use "required-features" to add binary-only features.
For example, "simple_logger" and/or "clap" should perhaps both be behind a feature called "tool" or "cli"?
https://doc.rust-lang.org/cargo/reference/cargo-targets.html#binaries
Basically, if someone uses the library only, they shouldn't need to have the extra dependencies that won't be used.