We are ignoring kombu.transport.librabbitmq because apicheck is failing
due missing librabbitmq library.

* Clean up grammar in paragraph about callbacks

* Structure event draining examples into subsections

* Make code example make more sense

… and bring it more in line with text above.

* Fix code example

* Fix another code example

typo in method name

* Fix tiny mistake in introduction

… at least I _think_ it's a mistake.

* Remove unused import in code example

* Fix minor grammatical errors

Co-authored-by: galcohen <gal.cohen@autodesk.com>

* sqs retry policy

* add test

* method definition

* add validation

* rename policy

* add kombu doc

* improve docstring

* add test and doc

* test fix

* test fixes

* add doc

* Update docs/reference/kombu.transport.SQS.rst

Co-authored-by: Omer Katz <omer.drow@gmail.com>

* Update docs/reference/kombu.transport.SQS.rst

Co-authored-by: Omer Katz <omer.drow@gmail.com>

* Update kombu/transport/SQS.py

Co-authored-by: Omer Katz <omer.drow@gmail.com>

* Update kombu/transport/SQS.py

Co-authored-by: Omer Katz <omer.drow@gmail.com>

* Update kombu/transport/SQS.py

Co-authored-by: Omer Katz <omer.drow@gmail.com>

* review improvements

* improvements

* add improvements

* rename

Co-authored-by: galcohen <gal.cohen@autodesk.com>
Co-authored-by: Omer Katz <omer.drow@gmail.com>
Co-authored-by: Asif Saif Uddin <auvipy@gmail.com>