s4: update What's new and explain how to upgrade a samba4 provision

WHATSNEW4.txt

@@ -65,7 +65,7 @@ directories.
 CHANGES SINCE alpha8
 =====================
 
-In the time since Samba4 alpha7 was released in Feburary 2009, Samba has
+In the time since Samba4 alpha8 was released in June 2009, Samba has
 continued to evolve, but you may particularly notice these areas 
 (in no particular order):
 
@@ -117,6 +117,9 @@ KNOWN ISSUES
   consult upgrading-samba4.txt.  We have made a number of changes in
   this release that should make it easier to upgrade in future. 
 
+- ACL are not set by default on shares created by the provision.
+  Work is underway on this subject and it should be fixed in Alpha10.
+
 RUNNING Samba4
 ==============
 

upgrading-samba4.txt

@@ -0,0 +1,24 @@
+Upgrading from an older samba4 installation.
+
+For users of samba4 alpha 8 and after
+=====================================
+
+* Stop any samba process
+* Backup your samba4 provision:
+  go in the directory where your samba4 provision is stored (/usr/local/samba by default)
+  do tar cf $HOME/backup.tar private (it's also recommended to save the etc/smb.conf and var/sysvol dir aswell)
+* Go in the source4 dir
+* run ./python/scripting/upgradeprovision
+* do make install
+
+For users of samba4 alpha 8 and after
+=====================================
+
+* Stop any samba/smbd process
+* Backup your samba4 provision:
+  go in the directory where your samba4 provision is stored (/usr/local/samba by default)
+  do tar cf $HOME/backup.tar private (it's also recommended to save the etc/smb.conf and var/sysvol dir aswell)
+* Go in the source4 dir
+* run ./python/scripting/upgradeprovision --full
+* do make install
+