In `bbp_merge_topic_handler()` delete last and count metas, and update the reply position after call to `wp_update_post()`. Fixes bug where merging two topics with odd timestamps could result in orphaned or incorrect meta data and hierarchy positioning. Props netweb. Fixes #2528.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5489 9866e705-20ec-0310-96e7-cbb4277adcfb
Remove remaining 'Reply To' references in reply `post_title`'s.

(Now that posts can have empty titles, this is no longer necessary. It also yielded undesired single reply slugs, though they are only exposed to moderators and keymasters.)

Hat tip netweb.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5490 9866e705-20ec-0310-96e7-cbb4277adcfb
In `bbp_split_topic_handler()` remove `$reply_position` cheater code, and rely on `bbp_update_reply_position()` to recalculate the correct position in the hierarchy after `wp_update_post()` has finished. Props netweb. Fixes #2624.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5491 9866e705-20ec-0310-96e7-cbb4277adcfb
Missed a 'Reply To' reply title update. See r5490.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5492 9866e705-20ec-0310-96e7-cbb4277adcfb