Add newer releases of handlebars

[florianpilz]

Version 1.3.0 is fairly outdated. I would like to use this PyPi package, but with a newer release. If you give me rights to the PyPi package I will gladly provide a pull request to introduce new versions. (My name on Pypi is florianpilz)

[florianpilz]

@mgood I am still interested to have the rights on Pypi to update the handlebars package. If you want, I would also transfer this repository to our company account gocept.