#836 - Clarify that createResource is just user code in the reference documentation.

src/main/asciidoc/server.adoc

@@ -469,6 +469,7 @@ class PersonModelAssembler extends RepresentationModelAssemblerSupport<Person, P
   }
 }
 ----
+NOTE: `createResource(...)` is code you write to instantiate a `PersonModel` object given a `Person` object. It should only focus on setting attributes, not populating `Links`.
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 Setting the class up as we did in the preceding example gives you the following benefits: