P is a permission list, then a UID x
matches the permission if it either appears in the list
P, or is a member of one of the groups that appear in
P.
An example of a permission list is
({ "frege", "dino", "$baboon" })
The UIDs that match this permission list are "frege",
"dino", and members of the group
"$baboon".
The following efuns work with permission lists.
int match_perm(mixed uid, string *perm)
uid can be an object or a UID. If it is
an object, the object's EUID is used. The function returns
1 if uid matches permission
perm, and 0 otherwise.