Update draft release notes to 1.7.8

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/RelNotes/1.7.8.txt

@@ -4,6 +4,8 @@ Git v1.7.8 Release Notes (draft)
 Updates since v1.7.7
 --------------------
 
+ * Some git-svn and git-gui updates.
+
  * The build procedure has been taught to take advantage of computed
    dependency automatically when the complier supports it.
 
@@ -147,7 +149,7 @@ included in this release.
 
 ---
 exec >/var/tmp/1
-O=v1.7.7-289-gb73c683
+O=v1.7.7-324-g47d45a5
 echo O=$(git describe --always master)
 git log --first-parent --oneline --reverse ^$O master
 echo