Set version number to 0.4.2.
Set version number to 0.4.2.

wkentaro/slacker,hreeder/slacker,kashyap32/slacker,os/slacker,olasitarska/slacker,techartorg/slacker,BetterWorks/slacker,STANAPO/slacker,dastergon/slacker,wasabi0522/slacker