enable changing debug and prefix by outside callers

logging/types.go

@@ -15,8 +15,8 @@ type Logger interface {
 	Info(string, ...interface{}) error
 	Notice(string, ...interface{}) error
 	Warning(string, ...interface{}) error
-	doDebug(bool)
-	setPrefix(string)
+	DoDebug(bool)
+	SetPrefix(string)
 	GetPrefix() string
 	Setup()
 	Shutdown()