o Rename internal library functions so that they are prefixed with
_posix1e or _POSIX1E, removing them from the application namespace (and
potential conflict with other ACL functions elsewhere in the system).
Obtained from: TrustedBSD Project
interface. This commit introduces the library, as well as a modest
subset of the ACL calls, with some modifications to support multiple
ACL semantics.
Reviewed by: eivind