find connections by name and number

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>
find devices by name and number

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>
0.4.0: get_dev/get_conn by name and number

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>
0.4.1: default timeout for connections

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>
0.5.0: make cmd() calls wait for running system

Signed-off-by: Erik Bernoth <erik.bernoth@gmail.com>