feat: aviator integration

[mumoshu]

https://github.com/JulzDiverse/aviator is basically a declarative wrapper around spruce. It is a tool to merge YAML files based on a config file aviator.yaml, and for merge operations you can use powerful spruce operators.

aviator advertises it as an alternative to helm, but it is true only for helm's templating functionality.

Integrating aviator into helm x allows you to turn any apps described as a aviator.yaml into a helm release, so that aviator + helm-x can be a complete alternative to the vanilla helm v2.