Refactor the ACL monitor interface to make full use of the monitor
command dispatcher. This also gives proper help formatting and command
completion. Note that 'acl allow' and 'acl deny' were combined to
'acl_add aclname match allow|deny [index]' for consistency reasons.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>