Issue #289504 by mikeryan, catch, moshe weitzman: backport indexes from Drupal 7 on comments and node_comment_statistics to improve performance of mass-user operations such as deleting users en masse

Issue #336483 by brianV, catch: add index for comment_count on column in node_comment_statistics to avoid full table scan when search index is updated for example

#360023 by greggles, rszrama, stella, sun, andypost: add missing comment publish action and clean up some code documentation

#396388 by jmpoure, Alex_Tutubalin, Shiny, andypost,: rework comment ordering subquery to be SQL standards (and therefore PostgreSQL) compatible

#673974 by sun: PHP notice when mass-unpublishing or deleting comments, and wrong form validation redirect

#334826 by maartenvg, Dave Reid, brianV: when editing an anonymous comment, the uid was set to NULL, which is not valid as a database value for the uid; set to zero

#310139 by fonant, c960657, pwolanin: drupal_urlencode() and Drupal.encodeURIComponent was used to encode query strings and other components it should not have been used for

#353328 by catch, BrianV: When a new commment is added, the redirection path should point to page, where the new comment is.

#395086 by Freso: call trim() before truncate_utf8() in comment module for better quality truncation.

#328977 by Dave Reid, hgmichna: comment_controls() form function lacks first form_state parameter, so passed values are incorrectly used

#253577 by Morbus Iff, nevergone: Allow setting comment timestamp in comment_save(). Enabled import scripts to import dates for comments.

#217957 by yched, quicksketch: header cell removal is broken when headers use colspans (and a little bit of performance improvement)

#216504 by mcarbone and webchick: comment table was not properly aliased in comment_render()'s count query, so db_rewrite_sql() was not working well on the query

#216515 by chx and myself: cached forms made all subsequent forms on the page cached (critical); and a comment op check was buggy

#204411 by chx, slightly modified: heal a possible MySQL import error when the anonymous user becomes broken

#199809 by theborg: comment templates were not checking status properly (fix notice, allows themes to theme in-preview comments differently)

#195161 by mcarbone with some modifications: only show 'login to post comments' if logging in actually lets you post comments

#189878 by O Govinda, keith.smith: comment module help updates, removing help on features which are not there, and adding help on Drupal 6's new per content type comment settings

#199336 by JirkaRybka: remove improper t() use in update code (update goes all in English, but there were some mistakes), and add messages to updates where there was no return value otherwise, so users know what happens in each update