Added OAuth to provisioner stop method

[gitlaura]

This change is

[trevj]

Let's quickly describe the format of the return type while we're at it...is it just:

{
  droplet: <droplet id, as a string>
}

?

[gitlaura]

Updated the return type to Promise since there isn't anything to return.

[trevj]

Sorry for the delay!

[gitlaura]

I updated provisioner.ts to separate the stop and destroyServer_ methods so that we can call destroyServer_ if there's a failure when creating a cloud server.

[trevj]

Rather than wrapping the whole function in a try/catch block you could make this a precondition-like block:

if (!this.state_.oauth) {
  return Promise.reject({
    'errcode': 'OAUTH_ERR',
    'message': 'Cannot destroy server - not logged into digital ocean'
  });
  ...
  ...
}

Actually...since this is a private method only called by stop, do you really need this check?

[gitlaura]

Agree that we don't need it. Made this change.

[trevj]

BTW, am investigating the Travis failures now...

[trevj]

👍