Handle Optional Values within Records

[SupermanScott]

Summary: This change allows for the use of optional fields, especially optional strings within a record. Prior to the change the only null check on value is in the public toConnectData method. This isn't sufficient when handling Avro Records. It is common to have a Record that has optional types within it.

[ConfluentJenkins]

Can one of the admins verify this patch?

[ghost]

It looks like @SupermanScott hasn't signed our Contributor License Agreement, yet.

Appreciation of efforts,

clabot

[ConfluentJenkins]

Can one of the admins verify this patch?

[ewencp]

ok to test

[ewencp]

@SupermanScott Basic changes seem good, left a couple of minor comments and it looks like it needs a merge/rebase.

[mageshn]

@SupermanScott I can help take this PR forward. There are few rebase issues that need to be sorted out since this PR is old. Otherwise, we can just work a new PR against master. WDYT?

[cla-assistant[bot]]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
0 out of 6 committers have signed the CLA.

:x: Michael G. Noll
:x: ewencp
:x: alexlod
:x: gwenshap
:x: ijuma
:x: sdreynolds

---

Michael G. Noll seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}