Ubuntu 12 04 fixes

This branch solves issues reported in #2 for ubuntu 12.04.

Moreover there is an additional commit (8551a8ec9b930cd5d6ec9d988446d51817b4dda2) which enables databag searches in chef solo (I'm using [this plugin](https://github.com/edelight/chef-solo-search)). The change is backward compatible since the attribute is false by default. Feel free to include or exclude it.