Rails4: replace deprecated find_all_by_* at WikiPage model

git-svn-id: http://svn.redmine.org/redmine/trunk@12533 e93f8b46-1217-0410-a6f0-8f06a7374b81
remove unneeded Relation#all from WikiPage#handle_redirects

git-svn-id: http://svn.redmine.org/redmine/trunk@12534 e93f8b46-1217-0410-a6f0-8f06a7374b81
Rails4: replace deprecated find_all_by_* at WikiPageTest

git-svn-id: http://svn.redmine.org/redmine/trunk@12535 e93f8b46-1217-0410-a6f0-8f06a7374b81