Should not prefix the environment name with anything

[rprieto]

Currently inspects the ZIP archive: <appname>-<version>.zip, then prefixes the target environment with <appname> to make it unique to the region.

This should be the responsibility of the calling code. It's especially confusing when using Beanstalkify alongside other AWS SDK code (ex: blue-green deployments), where you need to add manual prefixes only half the time.