Move multipoint mention into a note

Author: patrickhlauke

guidelines/terms/21/single-pointer.html

@@ -1,5 +1,6 @@
 <dt><dfn>single pointer</dfn></dt>
 <dd>
-   <p>an input that only targets a single point on the page/screen at a time – such as a mouse, stylus, or single finger on a touch screen – as opposed to multi-pointer/multi-touch scenarios</p>
+   <p>an input that only targets a single point on the page/screen at a time – such as a mouse, stylus, or single finger on a touch screen.</p>
+   <p class="note">In contrast to single pointer inputs, multipoint interactions involve the use of two or more pointers at the same time – such as two finger interactions on a touchscreen, or the simultaneous use of a mouse and stylus.</p>
 </dd>