Support vshard's `identification_mode` = `name_as_key`

[Totktonada]

It is released in vshard 0.1.25. See tarantool/doc#3942.

This mode has different vshard.storage.info() output: names are there instead of UUIDs.

At least the following crud's code is not ready for that.

crud/crud.lua

Lines 182 to 196 in a897f4c

	local box_info = box.info()
	local replicaset_uuid
	if box_info.replicaset ~= nil then
	replicaset_uuid = box_info.replicaset.uuid
	else
	replicaset_uuid = box_info.cluster.uuid
	end
	local replicaset_info = storage_info.replicasets[replicaset_uuid]
	if replicaset_info == nil or replicaset_info.master == nil then
	error(string.format('Failed to find a vshard configuration for ' ..
	' replicaset with replicaset_uuid %s.',
	replicaset_uuid))
	end
	user = luri.parse(replicaset_info.master.uri).login or 'guest'
	end

[DifferentialOrange]

As far as I understand, 0.1.25 with new mode enabled will break the crud module apart on initialization?

[Totktonada]

@DifferentialOrange I don't know, but I hope that the new mode is generally compatible with the old one. Only testing can tell us.