Better log messages during notifications

### Description
Made underlying thread during notifications to have the same transactionId as its father.
Added LM_I 'Notification Sucessfully Sent' for notifications.
The changes should cover both ontimeinterval and onchange.

Fixes issue #453 

Yeah, I've been thinking about this also.
Would probably do it as a macro though to avoid calling a function.
The same for transaction started, even though it is used only twice.

The reason for using strncpy instead of strcpy is that is is safer and a year from now you'll just run lint or do a grep and you'll find a 'strcpy'!

In this very case, strncpy is not necessary, we just use it to avoid problems.