Implement API methods of the Container contracts client corresponding
to the calls of the contract for storing the used space of the container
("putContainerSize", "getContainerSize", "listContainerSizes"). Extend
the wrapper over the client with methods abstracted from sidechen calls.
In particular, the method of storing the value will be used to record
the estimates of the used space of containers calculated by the network
participants.
Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>
