* Add html to rule S6850
* Add HTML documentation to S6850
Also improve the wording by replacing the term _header_ with the semantically correct _heading_ one.
* Split the rules tags
Also format the JavaScript sample with 2-spaces identation.
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Co-authored-by: ericmorand-sonarsource <ericmorand-sonarsource@users.noreply.github.com>
Co-authored-by: Eric MORAND <eric.morand@sonarsource.com>
Co-authored-by: Ilia Kebets <104737176+ilia-kebets-sonarsource@users.noreply.github.com>
