Enhancement request: Allow me to prevent admin_email changes

[desmith]

Subject says it all :) I would like a way to prevent changes to the admin_email option (the "Administration Email Address" on Settings -> General).

The first/most obvious way to do this, to me at least, would be to create a new define, similar to WP_SITEURL, that always overrides the value of admin_email. That seems more comprehensive, but would involve digging into a lot of different places. Another possible implementation is to add a filter to update_option_new_admin_email (in wp-admin/misc.php) that lets you abort that call early.