doc: Suggest to use git shortlog -s to show the author of changeset of this particular release.

(cherry picked from commit 57bfc6e6)

doc/release-howto.txt

@@ -51,9 +51,9 @@
 
     First make sure you git-commit-ed the ChangeLog all the version release related changes, then:
 
-    git tag -a -m "VLC Release RELEASE_VERSION" <RELEASE_VERSION>
+    git tag -a -m "VLC Release VERSION" <VERSION>
     (Create an annotated tag, you can skip -a if you used -m)
-    git push origin <RELEASE_VERSION>
+    git push origin <VERSION>
 
     (You are advised to play with it on the sandrox.git if you feel unconfortable)
 
@@ -85,5 +85,8 @@
  * Announce email
   - write something along the lines of previous releases
   - post in videolan-announce (moderated), vlc et vlc-devel
+    You are advised to add the author list for this version 'git shortlog -s PREVIOUS_VERSION..VERSION'
+    And to add git diff --stat PREVIOUS_VERSION..VERSION if it's relevant.
+    You can play a bit with git to show the piece of information that may be interesting.
   - add a sticky thread in the "General VLC media player discussion" forum