Automatic merge from submit-queue
Set Kubelet Disk Defaults for the 1.7 release
The `--low-diskspace-threshold-mb` flag has been depreciated since 1.6.
This PR sets the default to `0`, and sets defaults for disk eviction based on the values used for our [e2e tests](https://github.com/kubernetes/kubernetes/blob/master/test/e2e_node/services/kubelet.go#L145).
This also removes the custom defaults for vagrant, as the new defaults should work for it as well.
/assign @derekwaynecarr
cc @vishh
```release-note
By default, --low-diskspace-threshold-mb is not set, and --eviction-hard includes "nodefs.available<10%,nodefs.inodesFree<5%"
```