[patch] encrypted VSA support for freeradius-1.0.5

Hello, This patch adds support for encrypted VSAs to freeradius-1.0.5. This is necessary for some VSAs used by Juniper JUNOSe 6.x and later (ERX). The patch has been tested in our lab using the fore-mentioned salt-encrypted VSAs. Please let me know if this is inappropriate in some way (coding style, patch contents, other). Bjørn