core (notes), common (symbol): added an icon showing note level: because of Symbol binding, it was difficult to precisely set the icon position, so Symbol has been modified to remove bindings. Added consts for INFO, WARNING and ERROR colors.

[DEFAULT]
bridge = pb
log_level = debug
log_fmt = #[%%(levelname)s][%%(name)s] %%(message)s

[cagou]
log_level = debug
log_fmt = [%%(levelname)s][%%(name)s] %%(message)s