Added neqn's description

git-svn-id: http://svn.linuxfromscratch.org/LFS/trunk/BOOK@756 4aa44e1e-78dd-0310-a6d2-fbcd4c07a689

appendixa/groff-desc.xml

@@ -142,7 +142,7 @@ standard output, and repeats this process until the end of input.
 <sect3><title>neqn</title>
 
 <para>
-It is currently not known what neqn is and what it does.
+The neqn script formats equations for ascii output.
 </para>
 
 </sect3>