Use rtf format files for legacy OS X installer builds.
(Backport from 3.4 changes for Issue #17128.)
diff --git a/Mac/BuildScript/resources/Welcome.rtf b/Mac/BuildScript/resources/Welcome.rtf
index e793abb..ea15e0b 100644
--- a/Mac/BuildScript/resources/Welcome.rtf
+++ b/Mac/BuildScript/resources/Welcome.rtf
@@ -20,13 +20,9 @@
 \b NEW for Python 2.7.9: 
 \b0 This package installs a version of 
 \f1 pip
-\f0 , the recommended tool for installing and managing Python packages.   Type\
-\
-	
+\f0 , the recommended tool for installing and managing Python packages.   Type 
 \f1 pip2.7 --help
-\f0 \
-\
-for an overview.  2.7.9 also includes a number of network security enhancements that may require changes to your Python applications.  See the 
+\f0  for an overview.  2.7.9 also includes a number of network security enhancements that may require changes to your Python applications.  See the 
 \f1 ReadMe
 \f0  file and {\field{\*\fldinst{HYPERLINK "https://docs.python.org/2/whatsnew/2.7.html#new-features-added-to-python-2-7-maintenance-releases"}}{\fldrslt the Python documentation}} for more information.\
 \