Conflicts:
	src/box/box_lua.cc
	test/big/iterator.result
	test/big/iterator.test
	test/big/lua.result
	test/big/lua.test
	test/box/lua.result
	test/box/lua.test

This patch limits maximum recursion depth for luaL_packsize and luaL_packvalue
functions to 16 nested tables. This check is needed to prevent a crash
on recursive Lua tables.

This patch adds lua_checkfield function - a wrapper for lua_tofield that raises
an error if Lua type can not be converted to lua_field structure. The function
should be used instead of lua_tofield in all bindings where custom types are not
supported.

A follow up fix for gh-72 in stable.
Set a savepoint on gc memory pool in lbox_print().

Print() output in Lua console used to go to the socket,
now it always goes to the log, just like in the binary port.
Remove the dead code responsible for setting up the environment
of print() so that its output could be captured and sent to the
client.

Conflicts:
	include/palloc.h
	src/box/box_lua.cc
	src/lua/init.cc
	test/wal/lua.test

This commit also converts Lua bindings for MsgPack to C++ because they
requires tbuf and region guard.

Merge gh-91, gh-118

Conflicts:
	src/box/tuple.cc

Merge gh-90.

Conflicts:
	client/tarantool/tc.c
	client/tarantool/tc_query.c

Also don't call sfree_delayed if snapshot process isn't started, closes #118

(Merge remote-tracking branch 'origin/master' into gh-121-travis1)

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

This commit also allows box.tuple.new() without arguments

Conflicts:
	client/tarantool/tc_opt.c