Non-hardcoded configuration - use `configure_me`?

[Kixunil]

Hardcoding configuration makes it annoying to debug things. I suggest to use my crate configure_me to do that and offer making a full PR as well as adding required features (subcommand support) to the library. The primary advantage of configure_me is support of config files and dirs out of the box. configure_me is used in electrs among other projects.

structopt vs configure_me

Common properties

• Declarative syntax
• Parse and validate Rust types - no manual conversion
• Correct support of non-uf8 paths (Path{Buf}, OsStr{ing}); I think structopt requires enabling this explicitly?
• Generate help page
• Environment variable support

Advantages of configure_me

• Support of config files and dirs with ability to override things and include files from arguments
• Generate man pages
• Explicitly correct GNU-style params/switches (--key val, --key=val, -xyzkval...; maybe structopt is still good enough?)
• Toml file enables processing by external tools
• MSRV will always support the Rust version available in Debian stable

Advantages of structopt

• Not using Toml makes it work with IDEs and the struct is more obvious
• Generate shell completions
• Mature and popular
• Native subcommand support (this should be irrelevant here since I'm willing to add support)

Disclaimer: I may be missing some things, feel free to point out/ask.