* Switch to dep for vendoring, update vendored libs
* [#2] Implement obfuscation of secrets in output #3
* This is a **breaking change**: The new default is to obfuscate the secrets in the output which means software relying on having secrets embedded in the output need to adopt for this using the `-o none` parameter to disable obfuscation.
This version introduces a breaking change: The vault keys are no longer provided as arguments to the command but as parameters. Also this introduces the potential to supply multiple vault keys. Their contents will be combined and supplied as environment variables to the executed command or the export statements.