A number of doc updates have been applied to the website. For the 2.6.1 release, resync Kafka's docs folder with the website.
Reviewers: Bill Bejeck <bbejeck@gmail.com>
Added re-direct for new page and added link to Developer Guide page
Reviewers: Matthias J. Sax <mjsax@apache.org>, Sophie Blee-Goldman <sophie@confluent.io>,
Adds web page docs for KIP-247
Author: Matthias J. Sax <matthias@confluent.io>
Reviewers: Guozhang Wang <guozhang@confluent.io>, Bill Bejeck <bill@confluent.io>, Joel Hamill <joel@confluent.io>, Damian Guy <damian@confluent.io>