Fix log configuration

Polipo installed on Ubuntu, after being restarted with the Chef generated configuration, will try to use `/var/log/polipo` as its log file.
It fails because the log directory `/var/log/polipo` was created during the first execution (before Chef conf generation).
This issue did not appear on Debian.

This fix keeps the Debian install working

Also, added a default box that will allow a `vagrant up` with no configuration