Start implementing Slog

[justinlatimer]

• Setup slog in the cli and psqlpack crates.
• Start using slog in the cli.
• Implement slog in the psqlpack library.
  • Allow usage of slog, std log crate or no logging.
  • Instrument the "package" operation.

Misc

• Set version and author for clap from cargo manifest.
• Remove an unused macro.
• Be explicit about the location of the cli bin source.
• Update dependencies.
• I updated rustfmt and kind of regret it :-/

[justinlatimer]

Implements #59

[justinlatimer]

YOLO