#15543: glossary entry for and 'universal newlines', and links to it.

Patch by Chris Jerdonek.
diff --git a/Doc/reference/simple_stmts.rst b/Doc/reference/simple_stmts.rst
index ce22b67..a9766a4 100644
--- a/Doc/reference/simple_stmts.rst
+++ b/Doc/reference/simple_stmts.rst
@@ -1024,5 +1024,5 @@
 .. rubric:: Footnotes
 
 .. [#] Note that the parser only accepts the Unix-style end of line convention.
-       If you are reading the code from a file, make sure to use universal
-       newline mode to convert Windows or Mac-style newlines.
+       If you are reading the code from a file, make sure to use
+       :term:`universal newlines` mode to convert Windows or Mac-style newlines.