Explicitely adds Berkshelf as a dependency in Gemfile

Without it rspec cannot complete.
Declares Upstart config before declaring the service

When converging, Chef looks for /etc/init/statsd.conf to create
the service. The file hasn't been created yet which ends up throwing
an exception.
Updates Berksfile to point to the new Chef supermarket.
Merge pull request #23 from cotap/service-init

Service init
Merge pull request #24 from cotap/supermarket

Updates Berksfile to point to the new Chef supermarket.