Document the Service source

[johngmyers]

Description

Adds reference documentation for the service source.

Checklist

• Unit tests updated
• End user documentation updated

[johngmyers]

/cc @mloiseleur

[mloiseleur]

Suggested change

	The domain names of the DNS entries created from a Service are sourced from the following places:
	The domain names of the DNS entries created from a Service are sourced following this plan:

[johngmyers]

I don't think "plan" is quite the right word. It is an algorithm, not a proposal. It does specify the locations where the data are sourced, so "places" isn't too far off, though the items do describe the act of adding instead of the data being added.

[mloiseleur]

Suggested change

	* If no DNS entries were produced for a Service by the previous steps
	2. If no DNS entries were produced for a Service by the previous step

[johngmyers]

This isn't the only place where items in the list depend on previous items not producing outputs. If we're going to take this sort of order-dependency as requiring a numbered list, we should do it consistently.

[mloiseleur]

/lgtm

[johngmyers]

/approve

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