Configurable PodUpload timeouts

[AdrianFarmadin]

The timeouts for PodUpload are hardcoded to 10s per connection and 120s for a request. This will cause problems for a large file transfer on slow network. It will be great to have these timeouts configurable.

public class PodUpload {
  private static final int DEFAULT_BUFFER_SIZE = 8192; 
  private static final int DEFAULT_CONNECTION_TIMEOUT_SECONDS = 10;
  private static final int DEFAULT_COMPLETE_REQUEST_TIMEOUT_SECONDS = 120;

https://github.com/fabric8io/kubernetes-client/blob/master/kubernetes-client/src/main/java/io/fabric8/kubernetes/client/dsl/internal/uploadable/PodUpload.java#L54
https://github.com/fabric8io/kubernetes-client/blob/master/kubernetes-client/src/main/java/io/fabric8/kubernetes/client/dsl/internal/uploadable/PodUpload.java#L87
https://github.com/fabric8io/kubernetes-client/blob/master/kubernetes-client/src/main/java/io/fabric8/kubernetes/client/dsl/internal/uploadable/PodUpload.java#L89