Add `meta_type` hinting to widget queries. See #2554.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5297 9866e705-20ec-0310-96e7-cbb4277adcfb
Add `meta_type` hinting to topics queries. See #2554.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5298 9866e705-20ec-0310-96e7-cbb4277adcfb
Add `meta_type` hinting to `bbp_update_forum_last_topic_id()`. See #2554.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5299 9866e705-20ec-0310-96e7-cbb4277adcfb
Add `meta_type` hinting to admin queries. See #2554.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5300 9866e705-20ec-0310-96e7-cbb4277adcfb
Add `meta_type` hinting to `bbp_move_reply_handler()`. See #2554.

git-svn-id: https://bbpress.svn.wordpress.org/trunk@5301 9866e705-20ec-0310-96e7-cbb4277adcfb