Add wait_for commands. Info to return named tuple

 * Add wait_for command to block until a remote command completes
 * Add wait_for_group to wait for a group
 * Changed client.info to return a list of namedtuple objects
Merge pull request #2 from ant1441/wait_for

Add wait_for commands & change client info to return named tuple
Rework fetching remote file
Merge pull request #3 from ant1441/get_file

Rework fetching remote file
Allow timeout arg on creating client
Merge pull request #4 from ant1441/timeout

Allow timeout arg on creating client