Added new category 'Issues' in forum;
Removed all discussions with category issue from main forum;
Added new category 'All Discussions' in forum;
Moved unknown/issue category to modelParser;
Fix Group Rating sort not working; Fixes #374
Merge pull request #445 from jerone/issue-435-issuesCategory

Issue 435 issues category

merge
Merge pull request #446 from jerone/issue-374

Fix Group Rating sort not working; Fixes #374

merge