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.

libyaml updated to upstream 0.1.6 (hg bce8b60f0b9a) in order to
fix heap overflow in yaml_parser_scan_uri_escapes.

This patch also revert our hack with extra identation of
flow-style sequences and maps at root level:

    setmetatable({10, 15, 20}, { __serialize="seq"})
    now encoded as
    "--- [10, 15, 20]\n...\n"
    instead of
    "---\n[10, 15, 20]\n...\n".

This trick is no more needed because REPL never uses flow mode
at root level.

This patch adds __serialize hook to sockets to fix REPL && admin console.

* Removed b64decode from box_net_box.lua
* Added base64_encode() and base64_decode() methods in digest
* Added base64 tests

Conflicts:
	test/box/bsdsocket.result
	test/box/bsdsocket.test

A superuser can not manage grants on not owned objects