Version 3.1.2

This is a bug fix release with some filter additions.

• Add ep_es_query_results filter.
• Add option to sync prior to shutdown.
• Readme update around WPCLI post syncing. Props @mmcachran
• Ignore sticky posts in find_related. Props @columbian-chris
• Weighting dashboard fixes around saving. @oscarsanchez
• Weighting UI improvements. Props @mlaroy