Group filters in the filter select list (#13849).

git-svn-id: http://svn.redmine.org/redmine/trunk@13662 e93f8b46-1217-0410-a6f0-8f06a7374b81
Moved format specific stuff on format specific methods.

git-svn-id: http://svn.redmine.org/redmine/trunk@13663 e93f8b46-1217-0410-a6f0-8f06a7374b81
Typo.

git-svn-id: http://svn.redmine.org/redmine/trunk@13664 e93f8b46-1217-0410-a6f0-8f06a7374b81