added 990 tag to Contents on Detail tab. fixes 495
added test for tag 990. fixes 495
added data record for test of 990 tag. fixes 495
changed 990 test to assertEqual
little tweak to test case, refs #495
little tweak to test case, refs #495
Merge pull request #521 from gwu-libraries/t495-add-99x-to-detailtab

T495 add 99x to detailtab