Fix Role::Channels to use error eventsets in join check method

	modified:   lib/IRC/Server/Pluggable/Protocol/Role/Channels.pm
Role::Channels; no need to use an EventSet for a single error ev

	modified:   lib/IRC/Server/Pluggable/Protocol/Role/Channels.pm
Add sanity to user_can(not)_join / user_can(not)_send

	modified:   lib/IRC/Server/Pluggable/Protocol/Role/Channels.pm
	modified:   lib/IRC/Server/Pluggable/Protocol/Role/Messages.pm