[1.5.X] Removed PHP references

Backport of 55a2d5b577 from master

docs/intro/overview.txt

@@ -257,8 +257,7 @@ lookup and function calls.
 Note ``{{ article.pub_date|date:"F j, Y" }}`` uses a Unix-style "pipe" (the "|"
 character). This is called a template filter, and it's a way to filter the value
 of a variable. In this case, the date filter formats a Python datetime object in
-the given format (as found in PHP's date function; yes, there is one good idea
-in PHP).
+the given format (as found in PHP's date function).
 
 You can chain together as many filters as you'd like. You can write custom
 filters. You can write custom template tags, which run custom Python code behind

docs/intro/tutorial01.txt

@@ -81,12 +81,12 @@ work, see :doc:`Troubleshooting </faq/troubleshooting>`.
 
 .. admonition:: Where should this code live?
 
-    If your background is in PHP, you're probably used to putting code under the
-    Web server's document root (in a place such as ``/var/www``). With Django,
-    you don't do that. It's not a good idea to put any of this Python code
-    within your Web server's document root, because it risks the possibility
-    that people may be able to view your code over the Web. That's not good for
-    security.
+    If your background is in plain old PHP (with no use of modern frameworks),
+    you're probably used to putting code under the Web server's document root
+    (in a place such as ``/var/www``). With Django, you don't do that. It's
+    not a good idea to put any of this Python code within your Web server's
+    document root, because it risks the possibility that people may be able
+    to view your code over the Web. That's not good for security.
 
     Put your code in some directory **outside** of the document root, such as
     :file:`/home/mycode`.

docs/intro/tutorial03.txt

@@ -235,11 +235,11 @@ be used to identify the matched pattern; and ``\d+`` is a regular expression to
 match a sequence of digits (i.e., a number).
 
 Because the URL patterns are regular expressions, there really is no limit on
-what you can do with them. And there's no need to add URL cruft such as ``.php``
--- unless you have a sick sense of humor, in which case you can do something
-like this::
+what you can do with them. And there's no need to add URL cruft such as
+``.html`` -- unless you want to, in which case you can do something like
+this::
 
-    (r'^polls/latest\.php$', 'polls.views.index'),
+    (r'^polls/latest\.html$', 'polls.views.index'),
 
 But, don't do that. It's silly.