[15] RFR: 8191395: policy.allowSystemProperty and policy.expandProperties also apply to JAAS configurations

[Sean Mullan]

Please review this small change to the documentation of these two 
security properties.

webrev: http://cr.openjdk.java.net/~mullan/webrevs/8191395/webrev.00/
bug: https://bugs.openjdk.java.net/browse/JDK-8191395
Thanks,
Sean