chore(docs): fix padding/outline on body

Closes #306.
Update Changelog.md
refactor(tabs): simpler code, focus fixes
fix(ripple) - properly activate pointer listener.
fix(ripple): ripple container self-removal NPE fixed.
fix(material-radio): Radio button a11y

Closes #310
fix(material-toolbar): Demo correct heading levels
fix(linear-progress): add basic aria support

This fix adds support for aria-valuemin, aria-valuemax and
aria-valuenow. The valuemin and valuemax attributes are static and thus
added during the compile phase. The valuenow attribute is updated as
the progress bar’s value attribute changes.

This commit relates to issue #297
Activate animation now uses transform instead of top/height
First shift to transforms for animation.

More to go…
Query animation is now transform-based

-Shrinking the radial gradient circles a bit to improve the visual
firefox and safari.
All animations now using transforms.
Using the transform mixin.
Add tests for linear progress