Verduidelijk gebruik van officiele Nederlandse termen (#244)

Er is geregeld onduidelijkheid over het gebruik van Engels in API's.
Deze regel is geschreven om verwarring bij vertalingen te
voorkomen als het om officiele Nederlandse termen gaat die
bijvoorbeeld in wetteksten zijn gedefinieerd.

Maak dit explicieter door naar wetteksten en officiele
overheidscommunicatie te refereren.

Author: TimvdLippe

sections/designRules.md

@@ -76,8 +76,9 @@ A resource that corresponds to a single conceptual entity is referred to as a [=
       </dd>
       <dt>Rationale</dt>
       <dd>
-         The exact meaning of concepts is often lost in translation. Publishing an API for an international audience might also be a reason to define interfaces in English.
-         Note that glossaries exist that define useful sets of attributes which SHOULD preferably be reused. Examples can be found at <a href="http://schema.org/docs/schemas.html">schema.org</a>.
+         <p>If your API references terms used in law or official government communication for example, then these terms have a well-defined meaning. The exact meaning of concepts is often lost in translation, hence such terms SHOULD be defined in the Dutch language.
+         <p>Publishing an API for an international (e.g. European) audience might be a reason to define interfaces in English instead.
+         <p>Note that glossaries exist that define useful sets of attributes which SHOULD preferably be reused. Examples can be found at <a href="http://schema.org/docs/schemas.html">schema.org</a>.
       </dd>
    </dl>
 </div>