Included additional options used by the SystemD generator
Included additional options used by the SystemD generator

* "usewrapper" decides whether the service script will use the wrapper script the SystemV generator uses, or rely on SystemD lifetime tracking
* If we're not uwing the SystemV wrapper, we need to pass the environment "env" to the generator, which was before passed only inside the wrappercode

RazZziel/node-linux,emdarcher/node-linux,coreybutler/node-linux,zonetti/node-linux,RazZziel/node-linux,zonetti/node-linux,coreybutler/node-linux,emdarcher/node-linux