Run `go vet` as part of Travis build
Merge pull request #116 from modcloth/add-go-vet-to-travis-build

Run `go vet` as part of Travis build
Merge pull request #115 from AudriusButkevicius/hidehelp

Make help command optional
Merge pull request #114 from AudriusButkevicius/shortcut

Add App.RunAndExitOnError shortcut
Merge pull request #112 from AudriusButkevicius/swap

Add Args.Swap command for swapping arguments