Add containerArchive() and containerArchiveStream() methods and deprecate containerCopy() and containerCopyStream()

[clue]

// old: deprecated
$promise = $client->containerCopy($container, $path);
$stream = $client->containerCopyStream($container, $path);

// new
$promise = $client->containerArchive($container, $path);
$stream = $client->containerArchiveStream($container, $path);

Builds on top of #47 and #42
Resolves #41