Add NullHandler.
Add NullHandler.

narfdotpl/logbook,redtoad/logbook,alonho/logbook,fayazkhan/logbook,FintanH/logbook,alex/logbook,mitsuhiko/logbook,alex/logbook,Rafiot/logbook,mbr/logbook,DasIch/logbook,maykinmedia/logbook,redtoad/logbook,mbr/logbook,omergertel/logbook,pombredanne/logbook,dvarrazzo/logbook,dommert/logbook,DasIch/logbook,alonho/logbook,maykinmedia/logbook,omergertel/logbook,Rafiot/logbook,dvarrazzo/logbook,alonho/logbook,RazerM/logbook,Rafiot/logbook,DasIch/logbook,omergertel/logbook,fayazkhan/logbook