Add support of several bridge types

valid_ipv4addr: Allow 0 in last byte. (closes: #33795)

valid_ipv4addr: Allow 255 in 2nd and 3th bytes.

Drop unneeded line.
Add functions for read current default route and DNS settings.
Suppress 'broken pipe' error message.
Add list_bridge() and list_bridge_with_cache().
Add function for host interfaces.
list_iface(): Skip ifaces in a bonding.
list_eth(): Don't replace interface with bridge.
Add init_slave_eth_iface_cache().
Add warning for deprecated functions.
Remove read_iface_slaves().
Add remove_iface_with_cache().
Add list_vlans_for_iface() and list_vlans_for_iface_with_cache().
iface_has_host(): Suppress find's error messages.
Add list_vlan() and list_vlan_with_cache().
Introduce function for work with cached data.
next_iface(): Pass ifaces directory as argument.
list_network(): Pass ifaces directory as second argument.
Use list_etcnet_iface_filtered() to list interfaces.
Use list_etcnet_iface_filtered for list_ppp().
Add functions for filtered interfaces list.
iface_has_host: Handle VLAN interfaces too.
Rename read_iface_slaves -> read_iface_host_var.

Fix valid_ipv4addr().

Add read_iface_slaves() and iface_has_host() functions.
Add list_bond() function.

Improve is_ipv6_enabled() (thx stanv@).

Added is_ipv6_enabled() function.

refdns: Replace valid_ipv4() with valid_ipv4addr().
Added valid_ipv4addr() function.
Added tests for ipv6addr_is_in_subnet() function.
Added get_ip_version() function.
revdns: Added IPv6 support.
Added ipv6addr_is_in_subnet() function.
ipv6_network(): Use valid_ipv6prefix().
Added valid_ipv6prefix() and valid_ipv4prefix() functions.

Update tests for IPv6 functions.
ipv6addr_expand(): Expand each segment of IPv4 address.
Improve ipv6addr_terse().
Rename ipv6add_terse -> ipv6addr_terse.

added initial IPv6 support (sem@)

add multiple interface addresses support

add ipv4addr_prefix_to_mask() (maskname replacement)
remove obsolete functions:

fix ipv4addr_is_in_subnet().

add a new set of excellent functions for various ipv4address calculations (sem@)

list_iface: skip ifaces with type=801 (wmaster0) (closes: #19866)