This patch adds the option to set a nodeport when creating a NodePort
service. In case of a port allocation error due to a specified port
being out of the valid range, the error now includes the valid
range. If a `--node-port` value is not specified, it defaults to zero, in
which case the allocator will default to its current behavior of
assigning an available port.
This patch also adds a new helper function in `cmd/util/helpers.go` to
retrieve `Int32` cobra flags.
**Example**
```
$ kubectl create service nodeport mynodeport --tcp=8080:7777 --node-port=1
The Service "mynodeport" is invalid: spec.ports[0].nodePort: Invalid
value: 1: provided port is not in the valid range. Valid ports range
from 30000-32767
$ kubectl create service nodeport mynodeport --tcp=8080:7777 --node-port=30000
service "mynodeport" created
$ oc describe service mynodeport
Name: mynodeport
Namespace: default
Labels: app=mynodeport
Selector: app=mynodeport
Type: NodePort
IP: 172.30.81.254
Port: 8080-7777 8080/TCP
NodePort: 8080-7777 30000/TCP
Endpoints: <none>
Session Affinity: None
No events.
```
Most of our communications from apiserver -> nodes used
nodutil.GetNodeHostIP, but a few places didn't - and this
meant that the node name needed to be resolvable _and_ we needed
to populate valid IP addresses.
Fix the last few places that used the NodeName.
Issue #18525
Issue #9451
Issue #9728
Issue #17643
Issue #11543
Issue #22063
Issue #2462
Issue #22109
Issue #22770
Issue #32286
KubeletClient implements ConnectionInfoGetter, but it is not a complete
implementation: it does not set the kubelet port from the node record,
for example.
By renaming the method so that it does not implement the interface, we
are able to cleanly see where the "raw" GetConnectionInfo is used (it is
correct) and also have go type-checking enforce this for us.