Fix documentation for AbstractStyle and StyleInterface
Extend \Mibew\Plugin\PluginInterface
Add \Mibew\Plugin\AbstractPlugin class
Rename StyleInterface::filesPath method to "getFilesPath"
Rename "StyleInterface::name" method to "getName"
Rename "StyleInterface::configurations" to "getConfigurations"
Rename StyleInterface::availableStyles to "getAvailableStyles"
Use "get" prfix for AbstractStyle::defaultConfigurations
Use "get" prefix for StyleInterface::currentStyle
Use "get" prefix for StyleInterface::defaultStyle