Automatic merge from submit-queue

Use correct home directory on Windows

As of now the `kubectl` config mechanism that saves/loads `~/.kube/config` is broken on Windows, saving the config file in the *current* directory instead of the user's *home* dir. This happens because most Windows don't respect the `HOME` environment variable. 

This PR changes the config file loading mechanism to use the recommended way to detect the user home on Windows (`HOMEDRIVE`+`HOMEPATH` or `USERPROFILE`), and adds a migration for users that might be currently relying on existing config files.