Higher timeout and two tries for update packages

For the yum/apt upgrade exec increase the timeout
from the default 5 minutes to 15 minutes and do
two tries.

Change-Id: I6687e7768862ab0471714392b358ac423f31ef72

manifests/repos.pp

@@ -131,6 +131,8 @@ class openstack_integration::repos {
   exec { 'update-packages':
     command     => $update_cmd,
     refreshonly => true,
+    tries       => 2,
+    timeout     => 900,
   }
 
 }