Stack can't be overflow by box.net.box operations.

remote:call always returns lua-table.
Localize variables in box.net.box procs.
Merge branch 'master' of github.com:tarantool/tarantool into lua-stack-in-net-box

Conflicts:
	test/replication/consistent.test.lua
	test/replication/hot_standby.result
	test/replication/hot_standby.test.lua
remote.rpc namespace.
Merge branch 'master' of github.com:tarantool/tarantool into lua-stack-in-net-box
Drop 'unpack's from tests.