[WIP][ticket/12813] Improve responsive pagination alignment and page-jump fixes

1. Fix incorrect title attribute on page-jump input element
2. Remove empty value attribute on page-jump input element
3. Use input type="number" for page-jump
4. Reduce the number of page elements in the topic-row pagination
5. Reposition topic-row pagination on the same line as "replies", thereby giving more room to the last-post info.

https://tracker.phpbb.com/browse/PHPBB3-12813
Update, I decided to use `-moz-padding-end: inherit;` instead. So this is now a FF-only fix.