Change code to make last token useable only, as suggested by Lukas:

17/12/14: It seems that multiple tokens can be sent to the same admin/SP pair and all of these tokens then can be used.


git-svn-id: https://svn.geant.net/GEANT/edugain_testidp_account_manager/trunk@83 047e039d-479c-447e-8a29-aa6bf4a09bab