Fixed bad endpoint names (sorry) and some cleanup

* removed https module... wasn't used
* changed `lead_status` and `opportunity_status` to `status.lead` and `status.opportunity` respectively to fit in the rest of the API (ie. `activity.note`) and reflect the actual URL path
* used a jslinter
* https://github.com/airbnb/javascript#variables changed how variable were declared
* added an assert to the lead creation/update/delete test

Also - How come we can't make issues? Would be nice to be able to talk to you guys :)