paginate_links outputs unnecessary dots

[rphelan]

Steps to reproduce:

A) Call paginate_links with current=2, total=6

B) Call paginate_links with current=5, total=6

(assume defaults for everything else: mid_size=2, end_size=1, show_all=false)

Actual results:

A) [1] ... [3] [4] [5] [6]

B) [1] [2] [3] [4] ... [6]

The output includes dots that are unnecessary because they are taking up space that an actual page link could occupy.

Expected results:

A) [1] [2] [3] [4] [5] [6]

B) [1] [2] [3] [4] [5] [6]

When total <= mid_size + end_size * 2 + 2, no dots should be included in the pagination output.

[afercia]

Removing the accessibility focus, as per today's accessibility bug scrub. While this could be certainly improved, the dots don't introduce specific accessibility issues. While paginate_links() doesn't output fully accessible HTML by default, it can be used in an accessible way using for example prev_text and next_text, which is already done in some places in core.