Fix get_template_part() bug

Even if we don't want to set a path, we still need a name, so it doesn't
make sense to have $path first: get_template_part( 'name' ) makes more
sense than get_template_part( null, 'name' )
Add Search Parts AJAX feature
Fix bug
Fix bug
Add Search Part AJAX feature
Use new get_template_part() function
Upgrade query to reflect database improvement
Add IDs and classes for ajax calls