Update Lua and Luasocket version in samples and in documentation
Documented ipv5_v6only default option being set
Documented tcp6 and udp6
Documented dns.getaddrinfo
Documented zero-sized datagram change?
Documented getoption
Implemented new distribution scheme.
Select is now purely C.
HTTP reimplemented seems faster dunno why.
LTN12 functions that coroutines fail gracefully.
Update get.lua to use the new callbacks.
The old "code" module is now the "mime" module.
Updated all modules that depended on it.
Updated url.lua to use the new namespace scheme, and moved the
escape and unescape functions that used to be in the code.lua module
to it, since these are specific to urls.
Updated the callback entries in the manual.
