Update Normalize.css to v7.0.0

[mtomas7]

I condensed similar styles as it was in previous _s version, but if needed I have normal version too. Personally, I prefer the normal version, as it makes much easier to compare with the original Normalize.css source.

[grappler]

@mtomas7 Thanks! Could you also update sass/_normalize.scss too?

Just for future reference the lone modification that was made before #895 has been fixed upstream so we should be ok in updating. necolas/normalize.css@fe56763

[mtomas7]

Sorry, but I only worked with LESS, perhaps someone else with more experience could do this?

[grappler]

From the looks of the sass/_normalize.scss file it is the same as the CSS so you don't need to know Sass to update it. In #1144 we were discussing about adding the version number to the Normalize header of the style.css.

[davidakennedy]

@mtomas7 Any interest in updating things here? Thank you!

[crunnells]

#1272 supercedes this PR, bringing us up to v8.0.0. Thanks for your initial work here @mtomas7!