remove trailing white-spaces from test/unit/project_nested_set_test.rb.
remove trailing white-spaces from test/unit/query_test.rb.
remove trailing white-spaces from test/unit/role_test.rb.
remove trailing white-spaces from test/unit/helpers/sort_helper_test.rb.
remove trailing white-spaces from test/unit/principal_test.rb.
remove trailing white-spaces from test/unit/helpers/search_helper_test.rb.
remove trailing white-spaces from test/unit/wiki_redirect_test.rb.
remove trailing white-spaces from test/unit/workflow_test.rb.
Rails3: replace deprecated 'after_destroy' method at Attachment model.
add test to destroy at unit attachment test.
