xF2 Add-on Word Count Search 2.11.0

• Only show "Rebuild thread word-count" job if thread word-count is supported (aka Threadmarks is installed).
• Rework back-end code to better isolate how threadmarks are used to populate a thread's word-count.
  • Allows easy replacement of how a thread's word-count is populated.

• Fix modified threads did not trigger search re-indexing on as expected

• Move filters & input selection into template macros for better re-use by other add-ons (Required for Watch Thread filtering support)
• Tweak layout to be more compact and use XF2 numberbox instead of input type="number"