Add TOML parser.

README.md

 
 * [PHP Dotenv](https://github.com/vlucas/phpdotenv) - Parse and load environment variables from `.env` files.
 * [Symfony Dotenv](https://github.com/symfony/dotenv)- Parse and load environment variables from `.env` files.
+* [Yo! Symfony TOML](https://github.com/yosymfony/toml) - A PHP parser for [TOML](https://github.com/toml-lang/toml). 
 
 ### Third Party APIs
 *Libraries for accessing third party APIs.*