Use tin to update the version number in package.json.
tin -v x.y.z
Then run the publish script
./publish.sh
afterwards don't forget to update the versions to be a prerelease of the next version, so if you just published 1.1.1 then:
tin -v 1.1.2-alpha
git add package.json
git commit -m 'update version to 1.1.2-alpha'
git push origin master