puppet nftables

rubocop:auto_correct results

support a different table name for 'nat'
- Some applications (such as libvirt) still use iptables to inject firewall
rules
- iptables will refuse to update tables that were initially created with nft
- This commit allows defining the name of the 'nat' table in order to avoid...

Fix IPv4 source address type detection

Before this patch, a rule like this:

```
nftables::simplerule { 'foo':
action => 'accept',
dport => 443,
proto => 'tcp4',
saddr => '192.168.1.10',
}
```

would incorrectly generate this rule:...

Fix IP version filter for IPv6 traffic

Prefix custom tables with custom- so they're loaded

Fix context name (removes dup)

Auto fill simple table configuration

Allow some other types of verdicts

Handle dport internally always as an array

Implement nftables:;simplerule::daddr

Allow IPv4 and IPv6 only rules

Add nftables::simplerule

Reload rules atomically

Background: The unit file for nftables on CentOS 8 contains:

```
ExecStart=/sbin/nft -f /etc/sysconfig/nftables.conf
ExecReload=/sbin/nft 'flush ruleset; include "/etc/sysconfig/nftables.conf";'
ExecStop=/sbin/nft flush ruleset
```...

Add comments for all the nftable::rules entries

For each nftable::rule this adds an extra concat fragment to
add a comment containing the name and order number for the rule.

The motivation here is to make the mapping from resulting rules back
to puppet code more obvious. When adding a new rule it should be more...

Relax nftables::set::type making it optional

This is needed in case nftables::set is passed raw configuration via
source or content.