Newly added triggers should not fire if used with Hysteresis

[tobster]

Not a big issue but maybe it can be "fixed" in future release :-)

I added the following new trigger

({TRIGGER.VALUE}=0 & {Template Router:active.sessions.prot[tcp].avg(#3)}>2000) | \
({TRIGGER.VALUE}=1 & {Template Router:active.sessions.prot[tcp].avg(#5)}>1500)

The "problem" was that the value never went higher than 1800 but also never went below 1500. So after adding the trigger it fired because it's a new trigger but never disappeared.
It took my quite a while to understand. To solve it I had to increase the lower limit above the actual value, wait until zabbix fixed the issue and changed back the lower limit to 1500.