ingress-ice-4.5.7

Add support for 'sessionid' cookie as alternative to "SACSID" cookie

SACSID already expires after 24 hours, whereas 'sessionid' cookie expires
after 2 weeks. So using 'sessionid' instead of SACSID improves the situation.
Using SACSID is still supported though to remain compatibility. This resolves
github issue #3.