add golint check and fix all golints

logs/log.go

@@ -492,9 +492,9 @@ func (bl *BeeLogger) flush() {
 }
 
 // beeLogger references the used application logger.
-var beeLogger *BeeLogger = NewLogger()
+var beeLogger = NewLogger()
 
-// GetLogger returns the default BeeLogger
+// GetBeeLogger returns the default BeeLogger
 func GetBeeLogger() *BeeLogger {
 	return beeLogger
 }
@@ -534,6 +534,7 @@ func Reset() {
 	beeLogger.Reset()
 }
 
+// Async set the beelogger with Async mode and hold msglen messages
 func Async(msgLen ...int64) *BeeLogger {
 	return beeLogger.Async(msgLen...)
 }