Merge pull request #565 from JFreegman/master

initialize name_length
network.h:
- global: added sock_t
- Networking_Core: added family (currently always AF_INET) and port
- sendpacket(): changed signature to require (Networking_Core *) instead of sock_t

*.c:
- sendpacket()-calls: replaced *->net->sock with *->net
network.h:
- IP: add in_addr_t as part of the union
- IP: rename IP to IP4
network.*:
- IP4: changed in_addr_t to struct in_addr for compatibility reasons
- IP6: added
- IPAny: added
- addr_resolve_or_parse_ip(): converts a string into an IPAny
network.h:
- added ipany_ntoa()

network.c:
- added ipany_ntoa()
- fixed formatting
Update TODO
fix autobuild (not built locally)
network.*:
- IPAny_Port: analogous to IP_Port
- ipport_equal: moved from DHT.c and adapted

DHTc.:
- ipport_equal renamed to ip4port_equal
caught by autobuild, missing net->sock to net change
- added missing include (autobuild warning)
tox.*, DHT.*;
- second set of *_bootstrap_ex() functions to allow addresses instead of IPs

network.h:
- new message ID for sending/receiving IPv6 nodes

DHT.*:
- get_close_nodes():
  - additional parameter to select which kind of nodes: IPv4 or IPv6

- sendnodes()/handle_sendnodes():
  - the IPv4 message must remain intact even when the Node_format structure (which embeds IP_Port) is expanded
  - added Node4_format to keep the structure "alive"
  - copying in/out of wider to smaller format required in sendnodes()/handle_sendnodes()
  - switch of Node_format from Node4_format to Node46_format by define
More stuff done in group chats.
tox.*, Messenger.*:
- initialisation: argument added to enable/disable ipv6 as socket

Messenger_test.c:
- initialisation: ipv4 hardcoded for now
- delegating IP resolution to DHT_bootstrap_ex()
move group chats to /toxcore
Start of group chats integration into the core.
tox.*, Messenger.*:
- initialisation: argument added to enable/disable ipv6 as socket

Messenger_test.c:
- initialisation: ipv4 hardcoded for now
- delegating IP resolution to DHT_bootstrap_ex()
Merge branch 'Integration' of https://github.com/FullName/ProjectTox-Core into Integration
Merge branch 'master' into Integration
group_chats.c:
- *->net->sock to *->net (like everywhere else :))
Merge pull request #567 from kigu/patch-2

Update TODO