fix to VIM::Task::child_tasks()
fix to VIM::Task::child_tasks()

10xEngineer/rbvmomi,frapposelli/vagrant-rbvmomi,10xEngineer/rbvmomi,logankimmel/rbvmomi,rapid7/rbvmomi,omar-infinio/rbvmomi,frapposelli/vagrant-rbvmomi,rapid7/rbvmomi,vmware/rbvmomi,rcorrieri/rbvmomi