[css-display] Tweak title, move paragraph (and tweak wording), for box-suppress.

Author: fantasai

css-display/Overview.bs

@@ -422,15 +422,7 @@ Automatic Box Type Transformations</h3>
 
 
 <h2 id='box-suppress'>
-Controlling box generation: the 'box-suppress' property</h2>
-
-	''display:none'' was historically used as a "toggle" to switch between displaying an element or not.
-	Making this reversible requires either setting up the CSS <a>cascade</a> properly,
-	or remembering what the display type was before it was set to ''none''.
-	To make this common use-case easier,
-	the 'box-suppress' property was defined to do the same thing,
-	so that toggling whether or not an element displays
-	can now be done without affecting its layout type when it <em>is</em> displayed.
+Toggling box generation: the 'box-suppress' property</h2>
 
 	<pre class="propdef">
 	Name: box-suppress
@@ -443,9 +435,19 @@ Controlling box generation: the 'box-suppress' property</h2>
 	Media: all
 	</pre>
 
+	The ''display: none'' value was historically used as a "toggle"
+	to switch between showing and hiding an element.
+	Making this reversible requires either setting up the CSS <a>cascade</a> carefully,
+	or remembering what the 'display' value was before it was set to ''none''.
+	To make this common use-case easier,
+	this module introduces the separate 'box-suppress' property to do the same thing,
+	so that toggling whether or not an element appears in the formatting tree
+	can now be done without affecting its display type when it <em>is</em> displayed.
+
 	If the computed value of 'display' is ''none'',
 	the computed value of 'box-suppress' is ''discard''.
 	Otherwise, the computed value is the specified value.
+	Values have the following meanings:
 
 	<dl dfn-type="value" dfn-for="box-suppress">
 		<dt><dfn>show</dfn>
@@ -479,7 +481,6 @@ Controlling box generation: the 'box-suppress' property</h2>
 
 	Issue: We welcome better naming suggestions on this property.
 
-
 <h2 id='run-in'>
 Run-In Layout</h2>