[ddclient] new chart

[onedr0p]

Special notes for your reviewer:

This takes a free-form config to configure ddclient.

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• Chart Version bumped
• Variables are documented in the README.md
• Title of the PR starts with chart name (e.g. [radarr])

[onedr0p]

This is a service-less app. common library looks to expect a service

[bjw-s]

This is a service-less app. common library looks to expect a service

Hmmz... well, it actually has a service.enabled flag, but the container that is being generated doesn't check for that flag when setting the ports causing it to fail when applying.