Add check for whether action is enabled at the start of POST and GET calls (in addition to on 'perform_action').
Fix surveys send survey action tests.
Disable action links if the action isn't disabled.
Fix test_show().
Pop-over explaining why action is disabled.
Merge branch 'feature/issue-467-add-earlier-action-enabled-checks' into develop-frontend
Merge branch 'develop-frontend' into feature/issue-460-javascript-app-widgets