[WIP]Upgrade Netty to 4.1.17

[zsxwing]

What changes were proposed in this pull request?

Submitted this PR to see if there is anything broken.

How was this patch tested?

(Please explain how this patch was tested. E.g. unit tests, integration tests, manual tests)
(If this patch involves UI changes, please attach a screenshot; otherwise, remove this)

Please review http://spark.apache.org/contributing.html before opening a pull request.

[SparkQA]

Test build #84226 has finished for PR 19829 at commit 14dbc71.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #84231 has finished for PR 19829 at commit 93632a0.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[ash211]

Looks like a fix for https://issues.apache.org/jira/browse/SPARK-19552 -- should that be reopened now that netty is deprecating 4.0.x so we can't do it "Later" anymore?

[zsxwing]

@ash211 Good call. I will reopen it.

[vanzin]

I prototyped this change internally for a different reason, and I chose to create an abstract class for all this boilerplate, which seems cleaner to me.

public abstract class AbstractFileRegion extends AbstractReferenceCounted implements FileRegion {

  @Override
  @SuppressWarnings("deprecation")
  public final long transfered() {
    return transferred();
  }

  @Override
  public FileRegion retain() {
    super.retain();
    return this;
  }

  @Override
  public FileRegion retain(int increment) {
    super.retain(increment);
    return this;
  }

  @Override
  public FileRegion touch() {
    return touch(null);
  }

  @Override
  public FileRegion touch(Object hint) {
    return this;
  }

}

[zsxwing]

Good point! Updated!

[SparkQA]

Test build #84668 has finished for PR 19829 at commit 94df9ae.

• This patch fails build dependency tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class MessageWithHeader extends AbstractFileRegion
• static class EncryptedMessage extends AbstractFileRegion
• public abstract class AbstractFileRegion extends AbstractReferenceCounted implements FileRegion

[SparkQA]

Test build #84669 has finished for PR 19829 at commit 9a07d2b.

• This patch fails build dependency tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #84670 has finished for PR 19829 at commit c7cffe9.

• This patch fails to build.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class MessageWithHeader extends AbstractFileRegion
• static class EncryptedMessage extends AbstractFileRegion
• public abstract class AbstractFileRegion extends AbstractReferenceCounted implements FileRegion

[SparkQA]

Test build #84671 has finished for PR 19829 at commit 96df5f2.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds the following public classes (experimental):
• class MessageWithHeader extends AbstractFileRegion
• static class EncryptedMessage extends AbstractFileRegion
• public abstract class AbstractFileRegion extends AbstractReferenceCounted implements FileRegion