make the box available + help Vagrant find the Puppet manifest
perlbox.pp renamed to init.pp in this commit: https://github.com/gauravk92/perlbox/commit/3b30602ea6a1992f420e0cb185da53beb940c93e#diff-60ae41fd0a31977447947f59940ee9a4L24
Merge pull request #1 from shedd/master

Help Vagrant find the Puppet manifest