Improve README example

Slim down the example code.

Fix module namespacing issue

Change ::vlog:: -> $crate::, generally doesn't affect the user side.

Improved README and example code

• No code implementation changes, just example code changes.
• Improvement to README.

Fixed Cargo publish

• Added badges from crates.io and docs.rs.
• Fixed Cargo.toml for publishing.

Initial release of Rust verbosity level based macros for logging

v0.1.0

Fix publish error (#5)