TOML for configuration and/or metadata

[denisdefreyne]

TOML is a configuration file format that can be easier to deal with than YAML, which is what Nanoc uses for configuration and item/layout metadata.

Nanoc could look for a nanoc.toml file as an alternative for nanoc.yaml, and read the configuration from there.

Additionally, TOML metadata sections (a.k.a. frontmatters) could be supported. Such metadata sections would be enclosed in +++ rather than ---, e.g.

+++
title = "About Myself"
tags = ["about"]
+++