Provide helmwave support

[zhilyaev]

Sure! A little info about Helmwave:
🌊 Helmwave is a pioneer in management helm chart.
It is a part of CNCF landscape. Helmwave has up to ~600 stars on GitHub and continues to grow, uniting engineers across the world.

Our community has asked to make an integration with gitops.
Helmwave could mention argocd-lovely-plugin in the documentation as a workaround for argocd community.
So that’s why we’ve created this PR #486 for the beginning. If you suggest other options - please guide us through them.

[Joibel]

How would you use helmwave within ArgoCD? A lot of the features of Helmwave would seem to be alternatives to ArgoCD, not ones you would use at the same time.

How would lovely plugin make use of Helmwave, how would you call it?

[zhilyaev]

helmwave build command will generate plandir in .helmwave/manifests/$release@$ns.yml format. Argocd should use these manifests to apply.

helmwave also supports 2 engines for templating values