paginate on discussion view
Merge branch 'master' of gitorious.org:lorea/threads
Refactored threads_list_replies function.
Added @override keyword at some actions and views
Updated to Elgg 1.8.16.
Fixed override documentation.
Merge branch '1.8' of gitorious.org:lorea/threads into 1.8

Conflicts:
	actions/discussion/delete.php
	views/default/annotation/group_topic_post.php
	views/default/discussion/closed.php
	views/default/forms/discussion/save.php
Removed deprecated functions use.
Fixed thread delete.
Unified version numbering to 1.8.
Merge branch 'release/1.8.0'