allow flash messages to be permanent
when a query cannot be loaded, let angular display an error message
add 'show' action to QueryPolicy
return a 404 when accessing a not-viewable query via the experimental API
simplify index action on exp.api work_packages_controller
add experimental-api query permission specs
add specs for QueryPolicy:show
no need to check for performed? in exp.api wp-controller
fix query_loading spec
Merge pull request #2040 from opf/fix/16705_private_queries_can_be_accessed_by_other_user_via_url

Fix/16705 private queries can be accessed by other user via url