+ Fix logrotate.d config. #473

Conflicts:
	src/lua/bsdsocket.cc
	src/lua/bsdsocket.lua
	test/box/bsdsocket.result
	test/box/bsdsocket.test

socket.tcp_server() changes:

 * Set nice fibers names for listener and clients
 * Use only one address for bind
 * Return single socket instead of wrapper
 * Add opts = {} to arguments
 * Automatically remove UNIX domain socket on server:close()

Other changes:

 * Fix buggy port number parsng for ipv6
 * Add peer address to accept() results like recvfrom()

Restore OOM test (TreeIndex moved to another arena).
Update digest.result (spaces)
Update net.box.result (line numbers).

memtx_arena is shared memory, so TreeIndex can't use it as is
(breaks snapshotting).

Conflicts:
	.travis.yml

The wal writer now allocates memory to encode a binary log row,
but never used to free it. Add fiber_gc().

Restore fiber_gc() in recovery, and also move index allocation
from runtime to memtx arena.

Minor fixes & cleanups.

 * Split parser and resolver in src/uri.rl
 * Extend URI parser grammar to fully support RFC3986
 * Add Lua bindings to URI parser
 * Implement proper DNS logic in coio_connect() /
   evio_service_bind()
 * Replace uri_to_string() with sio_strfaddr()

Prerequisite for #447

Drop redundant enums for IOVMAX.
Better names for message encode/decode functions.

xrow.h - a universal representation of Tarantool binary request/response,
either in iproto protocol (binary client/server protocol),
snapshot or binary log (xlog).

Add a throwaway spot memory pool to recovery.

Add a replacement for show palloc in 1.5, which I simply removed
with small allocator.

The code responsible for writing into a socket
in blocking mode was broken. And the socket was non-blocking
to begin with.