[css-text-4] Properly mark up 'text-align' even though bikeshed doesn't currently link to a property in a different level of the same spec.

Author: dbaron

css-text-4/Overview.bs

@@ -724,7 +724,7 @@ Alignment and Justification</h2>
 
 	Issue: Add final level 3 content
 
-	Add this value to text-align
+	Add this value to 'text-align'
 
 	<dl dfn-for=text-align dfn-type=value>
 		<dt><dfn>&lt;string&gt;</dfn></dt>
@@ -850,7 +850,7 @@ Character-based Alignment in a Table Column</h3>
 	Is it only in-flow text whose containing block is the cell?
 	Or is text within any in-flow descendants
 	in the block formatting context established by the cell considered?
-	If so, is it considered only as long as its text-align property
+	If so, is it considered only as long as its 'text-align' property
 	is consistent with the cell's?
 	(Consistent in the alignment character, or fully consistent?)</p>
 
@@ -914,7 +914,7 @@ Character-based Alignment in a Table Column</h3>
 
 	<p class="issue">Formally defining the intrinsic width contributions
 	of column-spanning cells with &lt;string&gt; values of
-	text-align is a complicated (although straightforward) extension
+	'text-align' is a complicated (although straightforward) extension
 	of the decisions made for intrinsic width contributions
 	of non-column-spanning cells;
 	this should also be formally defined.