Added command prefix option to config.yml

Signed-off-by: JWhy <jwhy@jwhy.de>
Implement getBehaviorManager() for main plugin class

Signed-off-by: JWhy <jwhy@jwhy.de>
Added prefixedCommand and regex mapping methods to behavior template

Signed-off-by: JWhy <jwhy@jwhy.de>
Implemented ChatListener

Signed-off-by: JWhy <jwhy@jwhy.de>