fix for entry data field race condition

logger.go

@@ -12,7 +12,7 @@ import (
 // LogFunction For big messages, it can be more efficient to pass a function
 // and only call it if the log level is actually enables rather than
 // generating the log message and then checking if the level is enabled
-type LogFunction func()[]interface{}
+type LogFunction func() []interface{}
 
 type Logger struct {
 	// The logs are `io.Copy`'d to this in a mutex. It's common to set this to a