Don't show menu item translation if user don't have administer menu permission

This request conflicts with #889880: menu item title translation permission. Probably the best solution is a feature request for i18n to introduce more granular permissions for the locale groups.

And here it is: #969086: Allow per-textgroup translation permission.

The above feature request has been moved to i18n 7.x, so this will have to wait for it.

About this specific feature I think the opposite is more likely, that "you don't want to give administer permissions to translators just to translate strings".

So the granular permissions feature sounds ok for D7, but I don't think we want this in D6

About this specific feature I think the opposite is more likely, that "you don't want to give administer permissions to translators just to translate strings".

Actually, we have the following use case in many site of ours: the administrator cannot administer menus but can translate the interface. ATM this would let him to alter all the menu item titles in any language different from the default one, which is a partial privilege escalation.

So the granular permissions feature sounds ok for D7, but I don't think we want this in D6

Ok, but let's leave the i18nmenu_node issue open: I see no reason not to support this use case if we can without too much hassle.

Obviously this will be exploited in the 7.x version of i18nmenu_node.