Remify using a build step instead of Sass
Prevent IE8 from getting rem values
Remove call to rem mixin in icon sprite CSS
De-remify mixins and extends
Add missing trailing semicolon
Merge branch 'master' of github.com:guardian/frontend into pixrem
Revert "De-remify mixins and extends"

This reverts commit 9f25cb3165fe7560b64e778be98fd9d4a9033469.

Conflicts:
	common/app/assets/stylesheets/module/_discussion-mixins.scss
Revert "Remove call to rem mixin in icon sprite CSS"

This reverts commit 63a11714b3e14ff253dc5880c7f25670c57291e1.
Merge branch 'master' of github.com:guardian/frontend into pixrem
 commit 63a11714b3e14ff253dc5880c7f25670c57291e1.

Conflicts:
	Gruntfile.js
Merge pull request #5507 from guardian/pixrem

Remify using a build step instead of Sass