2.0.0

This versions breaks backwards-compatibility

• Bump requirements for PHP to 5.3+, by using namespaces: 26bdd23
• Bump WordPress requirement to 3.9: 35f91f3
• Refactor the whole plugin. Splits up initialisation of the plugin, moves add_*() out of class constructor, etc.
• Simplify loading plugin textdomain.
• Added and updated README examples.
• Improve documentation.