Start Nintex workflow to approve publishing a major version of an item

We have a Nintex workflow which starts with the minor version, goes for multiple approvals and ends with publishing the major version by changing the approval status to "Approved"

But. Is it possible to start this Nintex workflow like the following way where we can start an OOTB approval workflow?@

The best advantage of using the above way is that user can just click on "Publish" and it will start an approval.

Or is there any OOTB way to kick off the workflow from item ribbon?

I also read the following explanation where we can achieve it through some custom coding but the client want to go for an easy way.

http://www.ilovesharepoint.com/2009/01/publish-major-version-declarative.html

PS : Yeah, they laughed at me saying why Nintex can't provide this feature when even an OOTB 2010 approval workflow can do it.