ref-manual: Edits to DL_DIR variable.

(From yocto-docs rev: 968d77db785cc27d502c837944c98656bbc3659e)

Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/ref-manual/ref-variables.xml

@@ -903,8 +903,9 @@ Core layer for images cannot be removed
                 <para>
                     You can safely share this directory between multiple builds on the
                     same development machine.
-                    For additional information on how the build process gets source files
-                    when working behind a firewall or proxy server, see the
+                    For additional information on how the build process gets
+                    source files when working behind a firewall or proxy server,
+                    see this specific question in the
                     "<link linkend='how-does-the-yocto-project-obtain-source-code-and-will-it-work-behind-my-firewall-or-proxy-server'>FAQ</link>"
                     chapter.
                 </para>