Update list of older git docs

Documentation/git.txt

@@ -42,9 +42,10 @@ unreleased) version of git, that is available from 'master'
 branch of the `git.git` repository.
 Documentation for older releases are available here:
 
-* link:v1.5.2.3/git.html[documentation for release 1.5.2.3]
+* link:v1.5.2.4/git.html[documentation for release 1.5.2.4]
 
 * release notes for
+  link:RelNotes-1.5.2.4.txt[1.5.2.4],
   link:RelNotes-1.5.2.3.txt[1.5.2.3],
   link:RelNotes-1.5.2.2.txt[1.5.2.2],
   link:RelNotes-1.5.2.1.txt[1.5.2.1],