Bump version to 4.2.1.
Bump version to 4.2.1.

sadiqmmm/lita,crimsonknave/lita,mcgain/lita,chriswoodrich/lita,litaio/lita,jimmycuadra/lita,jimmycuadra/lita,chriswoodrich/lita,jaisonerick/lita,brodock/lita,tristaneuan/lita,MatthewKrey/lita,liamdawson/lita,sadiqmmm/lita,crimsonknave/lita,byroot/lita,brodock/lita,mcgain/lita,jaisonerick/lita,tristaneuan/lita,litaio/lita,elia/lita,natesholland/lita,elia/lita,liamdawson/lita,byroot/lita,natesholland/lita,MatthewKrey/lita