[js] fix docs typos

[Marketionist]

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[Marketionist]

@mach6 @lukeis @titusfortner please review

[Marketionist]

Currently build in Travis failed with:

assert 'bob' == ''

(https://travis-ci.org/SeleniumHQ/selenium/jobs/187081577#L1338)

and

expected no Exception, got #<Selenium::WebDriver::Error::TimeOutError: timed out after 5 seconds (Unable to locate element: #oneline

(https://travis-ci.org/SeleniumHQ/selenium/jobs/187081595#L870)

So, it's definitely not because of the typos fixing in this PR.

[cgoldberg]

why remove double spaces from the license header in capabilities.js when the same text appears in nearly every source file (with the double spaces)? seems like an arbitrary change making things inconsistent.

[Marketionist]

I see your point @cgoldberg, agreed. Added back extra spaces in license for consistency. Please re-review and merge if ok

[cgoldberg]

👍 I don't have access to merge though

[Marketionist]

Thanks for reviewing!