Enhancement Graphite and router metrics

Hi,
I made a pull request to enhance routers metrics and graphite.
As you know graphite do not support tags, so I added and create new key for graphite
Like : 
```
lab-jpe1.Router.0.100-67-224-1.router.responses.2xx
lab-jpe1.Router.0.100-67-224-1.router.responses.3xx
lab-jpe1.Router.0.100-67-224-1.router.responses.4xx
lab-jpe1.Router.0.100-67-224-1.router.responses.5xx
lab-jpe1.Router.0.100-67-224-1.router.responses.xxx
lab-jpe1.Router.0.100-67-224-1.router.responses.CloudController.2xx
lab-jpe1.Router.0.100-67-224-1.router.responses.CloudController.3xx
lab-jpe1.Router.0.100-67-224-1.router.responses.CloudController.4xx
lab-jpe1.Router.0.100-67-224-1.router.responses.CloudController.5xx
lab-jpe1.Router.0.100-67-224-1.router.responses.CloudController.xxx
lab-jpe1.Router.0.100-67-224-1.router.requests_per_sec
```
Pleas format these these lines for indent consistency. Also we think it makes more sense to have a method `router_key` that you only call when the job is equal to Router. i.e. `key = router_key(key) if job == "Router"`. This will allow you to be more explicit.