Remove warning about Firefox 33 from @counter-style demo

[oslego]

Removes outdated warning about CSS @counter-style being supported only on Firefox 33.

[chrisdavidmills]

Hi Razvan! The change makes sense, if it is supported in more places now, but this doesn't appear to be the case. I've just tested it on Firefox, Chrome, Opera, Safari, and Edge, and it still doesn't appear to work anywhere except Firefox.

Have you got evidence to the contrary?

[oslego]

My reason for removing the warning was that Firefox 33 is outdated, not that the feature has widespread support.

Feel free to accept or reject the PR.

My thinking is that there are places better suited to inform users of browser support: caniuse.com/#search=counter-style or the support matrix on the @counter-style MDN page which links to this demo. I doubt the support warning in this demo file will be kept up to date, while other sources will be.

[chrisdavidmills]

OK, I get your reasoning, and think it makes sense. Thanks for the explanation. r+