added detailed rollup naming

This prepends the domain to the application name. Useful for NR accounts with multiple sites/domains
FYI: we follow WordPress' code standards for spacing rules. See the automated code review in https://github.com/GigaOM/go-newrelic/pull/14#issuecomment-55058415 and our overall code standards at http://kitchen.gigaom.com/2014/07/17/our-code-standards/ .