Exits with a non-zero value (1) on task failure
Merge pull request #6 from sthaha/fix-exit-codes

Exits with a non-zero value (1) on task failure
Verbose message when image creation fails

* Exits as soon as the image creation fails
* Verbose output when image creation fails
Merge pull request #9 from sthaha/img-create-failure

Verbose message when image creation fails