Remove various tests and utilities related to testing kubernetes support
Also removing the Kubernetes and DefaultStackOrchestrator from CreateOptions
and UpdateOptions, instead updating the flags to not be bound to a variable.
This might break some consumers of those options, but given that they've become
non-functional, that's probably ok (otherwise they may ignore the deprecation
warning and end up with non-functional code).
Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
