With the updated cobra depencendy, we're now passing a context
from the cmd to the called functions.
When creating a cluster, one can pass a Duration to the --timeout
flag, which will create a new context with a timeout.
In the two blocking functions, where we're waiting for the master nodes
(initializing master nodes and "normal" master nodes), we're now
checking for the context cancellation as well, which may be caused
by the timeout.
