Updated the list view and completed puzzles
* Fixed some layout issues in the header and footer

* Redesign of the puzzle list page to not have pagination links.  Now all puzzles are shown on one page and ordered by piece count.  

* Changed how completed puzzles are to be redone.  On the front page they can only be seen if they are recently completed.  On the list page they are only shown to players that can redo them.

* Removed random puzzles from front page.

* Puzzles are not shown as recently active unless a piece is joined.  Before, it only required to move a piece to be considered as recently active.

* Images for puzzles in the list views are lazy loaded.

* Add puzzle preview in opengraph meta for puzzle page.  Should help when linking to a puzzle from other sites.

* Completed puzzles that can be redone now no longer show the finished puzzle.