[css-rhythm-1] Flip order of descriptions in introduction to match order of features in specification, as requested by Tantek Çelik. Fixes #1152

Author: fantasai

css-rhythm-1/Overview.bs

@@ -37,18 +37,18 @@ Introduction {#intro}
 	is desired in many cases.
 	This level of the specification focuses on following cases.
 
-	* Adjust heights of line boxes to multiples of the specified length.
 	* Adjust heights of block-level boxes to multiples of the specified length.
+	* Adjust heights of line boxes to multiples of the specified length.
 
-	By controlling heights of line boxes,
+	By stacking blocks at multiples,
+	authors can align content across columns, pages, scroll-snapped bocks
+	or multiple blocks placed absolutely
+	to maintain vertical rhythm.
+
+	Also by controlling heights of line boxes,
 	lines of text in different fonts can create consistent visuals
 	to help readability.
 
-	Also by stacking such line boxes,
-	authors can align lines across columns,
-	pages, scroll-snapped blocks, or multiple blocks placed absolutely,
-	to produce vertical rhythm.
-
 	<div class="figure">
 		<a href="examples/snap-height.html">
 			<img src="images/snap-height-sample.png"></a>