v0.3.0 — Correctness and streamlined dependencies

• Adjust Display format of LocalRepoError::CommandFailed to use the std ExitStatus Display
• Do not suppress stderr from executed Git commands (except for the command run by LocalRepo::is_git_repo())
• CLI: Do not emit a redundant error message when git remote get-url fails
• Drop serde, serde-json, fancy-regex, and lazy-static dependencies
• Remove the GH_OWNER_RGX and GH_NAME_RGX constants
• Properly follow RFC 3986 when parsing username & password fields in www.github.com URLs
• Correct the accepted format for URLs that start with ssh:// (They need to separate the hostname from the path with a slash rather than a colon)
• Schemes & hostnames in URLs are now parsed case-insensitively
• Switch from clap to lexopt
• LocalRepo::for_cwd() now returns a new dedicated variant of LocalRepoError if the call to std::env::current_dir() fails