[gtk-doc] help: Mention a few files which explicitly shou ldn’t be in git

[Stefan Kost <stefkost src gnome org>]

commit 08d461d82bef06508de4308c0a91097d8ba650de
Author: Philip Withnall <philip withnall collabora co uk>
Date:   Fri Dec 19 14:05:22 2014 +0000

    help: Mention a few files which explicitly shouldn’t be in git
    
    https://bugzilla.gnome.org/show_bug.cgi?id=741764

 help/manual/C/index.docbook |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)
---
diff --git a/help/manual/C/index.docbook b/help/manual/C/index.docbook
index 9aac439..50d0ce7 100644
--- a/help/manual/C/index.docbook
+++ b/help/manual/C/index.docbook
@@ -578,12 +578,17 @@ make
       <title>Integration with version control systems</title>
 
       <para>
-        As a rule of the thumb, it's those files you edit, that should go under
+        As a rule of thumb, it's the files you edit which should go under
         version control. For typical projects it's these files:
         <filename>&lt;package&gt;.types</filename>,
         <filename>&lt;package&gt;-docs.xml</filename> (in the past .sgml),
         <filename>&lt;package&gt;-sections.txt</filename>,
-        <filename>Makefile.am</filename>
+        <filename>Makefile.am</filename>.
+      </para>
+      <para>
+        Files in the <filename>xml/</filename> and <filename>html/</filename>
+        directories should not go under version control. Neither should any of
+        the <filename>.stamp</filename> files.
       </para>
     </sect1>