Add Ability to Enable/Disable the Markdown Parser
`Converter::attr()` Improvement
Revert "`Converter::attr()` Improvement"

This reverts commit ff6fa4fa0bcb3050582dbb79c2faa3ccfdd8e920.
`Converter::strEval()` Improvement
Move Default Configuration Data to `manager` Folder

+ Fix bug in configuration output from mixed data (array and object).
Example:

~~~ .php
var_dump(Config::get('article.content_type'));
~~~