rake install with `Bundler.with_clean_env`
rake install with `Bundler.with_clean_env`

This allows you to install the extension when running with bundler.

This is especially useful if people use shell frameworks or have aliases
prefixing bundle exec for every rake command.

https://github.com/bundler/bundler/blob/dfdeb0f89e7e88fcdfd001da089f09af3a77d2b4/man/bundle-exec.ronn#L66

appsignal/appsignal-ruby,appsignal/appsignal,matrinox/appsignal-ruby,appsignal/appsignal-ruby,matrinox/appsignal-ruby,appsignal/appsignal-ruby,appsignal/appsignal,matrinox/appsignal-ruby,appsignal/appsignal-ruby