Removing deprecated attributes from HTML table snippet

[robingrindrod]

The HTML table snippet in UltiSnips/html.snippets has the border, cellspacing and cellpadding attributes. The cellspacing and cellpadding attributes have both been deprecated in the HTML5 spec. As far as I can see, the border attribute does not seem to deprecated according to the official spec but the Mozilla wiki seems to think it is. Removing it would bring it in line with pull request #314 and I'd guess the attribute is not widely used.

I'll create a pull request with them all removed as this would be my own personal preference but I'd love to hear other people's opinions.

[sedrubal]

Totally agree. Please replace XHTML snippets with HTML5

[lpil]

Seems this issue has been fixed.

I think it'd be good to replace XHTML with HTML5, I'd be very happy to merge that PR.