[admin] Only generate OAR comment property on node creation

Rakefile

@@ -189,6 +189,8 @@ namespace :oar do
             # by default, maintenance is YES when creating new resources
             command.concat(' -p maintenance="YES"')
           end
+          # by default, an Alive node has comment "OK"
+          command.concat(' -p comment="OK"')
         end
         command.concat(" -p ").concat( export.to_a.map{|(k,v)|
           if v.nil?

generators/lib/grid5000/node.rb

@@ -43,7 +43,6 @@ module Grid5000
         h['memcore']         = properties['main_memory']['ram_size']/properties['architecture']['smt_size']/MiB
         h['memcpu']          = properties['main_memory']['ram_size']/properties['architecture']['smp_size']/MiB
         h['memnode']         = properties['main_memory']['ram_size']/MiB
-        h['comment']         = properties['comment'] || "OK"
         properties["gpu"]  ||= {}
         h['gpu']             = properties['gpu']['gpu'] ? "YES" : "NO"
         properties["monitoring"] ||= {}