Describe the bug

Try to deny some of default lua functions like 'os.getenv' for #1937 (comment)
and ACL will ignore it.

To reproduce
Release os.getenv (if you want you can take os.clock) and add in ACL.xml in Default rights
<right name="function.os.getenv" access="false"></right>
Make a resource with code like

iprint(os.getenv("PATH"))
addBan()

and you'll got the same situation
image

Expected behaviour
Both functions must be deny.

Version
master