update debian/changelog for 0.4.2
update debian/changelog for 0.4.2

seabirdzh/disco,beni55/disco,simudream/disco,oldmantaiter/disco,mozilla/disco,pombredanne/disco,mwilliams3/disco,simudream/disco,mozilla/disco,simudream/disco,seabirdzh/disco,seabirdzh/disco,pombredanne/disco,mozilla/disco,simudream/disco,pombredanne/disco,ktkt2009/disco,discoproject/disco,beni55/disco,pooya/disco,ErikDubbelboer/disco,scrapinghub/disco,mwilliams3/disco,beni55/disco,ErikDubbelboer/disco,pooya/disco,oldmantaiter/disco,ktkt2009/disco,ErikDubbelboer/disco,mwilliams3/disco,pombredanne/disco,discoproject/disco,scrapinghub/disco,scrapinghub/disco,simudream/disco,pavlobaron/disco_playground,scrapinghub/disco,beni55/disco,ktkt2009/disco,beni55/disco,pavlobaron/disco_playground,ktkt2009/disco,discoproject/disco,mwilliams3/disco,pavlobaron/disco_playground,ErikDubbelboer/disco,mozilla/disco,mwilliams3/disco,discoproject/disco,seabirdzh/disco,pooya/disco,oldmantaiter/disco,discoproject/disco,pombredanne/disco,ErikDubbelboer/disco,pooya/disco,seabirdzh/disco,ktkt2009/disco,oldmantaiter/disco,oldmantaiter/disco,pavlobaron/disco_playground