Add Chromedriver to the service list rather than throwing an error

[christian-bromann]

Rather than throwing an error such as:

Error transforming ./conf.js:
>      chromedriver: 'C/my app/chromedriver.exe'
The option "chromedriver" is not supported in WebdriverIO. We advise to use the "wdio-chromedriver-service" instead.
For more information on this configuration, see https://www.npmjs.com/package/wdio-chromedriver-service.
all done.

We should add Chromedriver to the list of services, e.g.:

services : [
    ['chromedriver', {
        protocol : 'http',
        hostname : 'localhost', 
        port : 4444,
        path : 'C:/my app/chromedriver.exe'
    }],
]

[christian-bromann]

There is no need for having Chromedriver set up as a service at this point.