lv:classify/@desc whitespace normalization during macropass

This allows for nice formatting with newlines (to avoid excessively long
lines) without affecting the output.

* src/current/include/preproc/expand.xsl
  (preproc:expand lv:classify/@desc): Normalize lv:classify/@desc whitespace

src/current/include/preproc/expand.xsl

@@ -497,7 +497,8 @@
       </xsl:attribute>
     </xsl:if>
 
-    <xsl:sequence select="@*" />
+    <xsl:apply-templates mode="preproc:expand"
+                         select="@*" />
 
     <!-- force @keep on @terminate -->
     <xsl:if test="@terminate='true'">
@@ -510,6 +511,24 @@
 </xsl:template>
 
 
+<!--
+  Normalize whitespace for class descriptions
+-->
+<xsl:template mode="preproc:expand" priority="5"
+              match="lv:classify/@desc">
+  <xsl:attribute name="desc"
+                 select="normalize-space( . )" />
+</xsl:template>
+
+<!--
+  All other class attributes are copied verbatim
+-->
+<xsl:template mode="preproc:expand" priority="1"
+              match="lv:classify/@*">
+  <xsl:sequence select="." />
+</xsl:template>
+
+
 <!-- default lv:match/@on short-hand to assert on a value of TRUE -->
 <xsl:template match="lv:match[ not( @value
                                     or @anyOf