nfacct: check cmd line argument for singleness

It was possible to specify several equal options for list operation.

Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
nfacct: add filter in to the list operation

Filter feature is working through NFACCT_FILTER netlink attribute.
If kernel doesn't support it, client will not get an error
and silently will work as before.

This patch adds following command line arguments: counters, overquota,
bytes-quota, pkts-quota. Which could be used with list operation.
Combination of these command line options isn't allowed.

For example.
user@root:/#nfacct list counters
will show counters without byte/packet based quota
user@root:/#nfacct list reset overquota
will reset value for overquoted counters only

Signed-off-by: Alexey Perevalov <a.perevalov@samsung.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>