Bump version to 0.12.2
Bump version to 0.12.2

cantonyselim/mailboxer,modsaid/mailboxer,mailboxer/mailboxer,mailboxer/mailboxer,jarkadlec/mailboxer,roomaroom/mailboxer,mattherick/mailboxer,lacco/mailboxer,joshtate04/mailboxer,modsaid/mailboxer,shekibobo/mailboxer,mattherick/mailboxer,Design-Collective/mailboxer,afalone/mailboxer,Groovej/mailboxer,joshtate04/mailboxer,sai43/mailboxer,chepri/mailboxer,netbrick/mailboxer,Groovej/mailboxer,lacco/mailboxer,roomaroom/mailboxer,t27duck/mailboxer,chepri/mailboxer,sai43/mailboxer,t27duck/mailboxer,untitledstartup/mailboxer,cantonyselim/mailboxer,untitledstartup/mailboxer,netbrick/mailboxer,div/mailboxer,shekibobo/mailboxer,jason-wang-0401/mailboxer,jarkadlec/mailboxer,Design-Collective/mailboxer,jason-wang-0401/mailboxer,techstars/mailboxer