Fix stupid typo after de98d9fefb94137492ad8696c9da8c6289c171ea.
Merge pull request #456 from XhmikosR/patch-2

Fix stupid typo after de98d9fefb94137492ad8696c9da8c6289c171ea.
extras_popular.jade: Add jQuery Tablesorter plugin.

This allows us to sort the table.
Disable sorting for the empty `th`.
Add Bootstrap theme.