Pagination: improve accessibility

Created by: thbt

There is a few issue with the current implementation of accessibility for the pagination component

• When working with icons, you use both aria-label and .sr-only. It makes sense to use aria-label on a link, since it is standard and is supported by most screen readers, so we don't really need the .sr-only span.
• Using a screen reader, disabled pagination links are not announced as "disabled". They can't be focused but the screen reader can still browse them.
  • adding aria-disabled="true" to the link in the example would fix this issue.
• You suggest adding <span class="sr-only">(current)</span> for the currently visited link, but some screen readers (NVDA) will read it wrong when reading the pagination backwards (from last to first): consider 2 is selected, it will read 3 - current - 2 - 1.
  • Using aria-label="Page 2 (current)" or aria-current="true" would fix this issue.

Let me know what you think.