Allow triggers dynamically change the frequency of their items.

At trigger configuration, add an option :  PROBLEM interval check 

At this option accept a interval data, just like the items. 

When the trigger become to PROBLEM state, the items used by them should dynamically change theirs frequency to the value set at the field "PROBLEM interval check" . 

Why? Is very common have items where they interval don't need to be short like 2 minutes or they have custom intervals for moments like out of worktime where we change the check to higher values like 20 minutes.

When a PROBLEM start, you should be notified soon as possible when they are SOLVED and for items with high intervals this is too long. So is very useful if we can force it to check more frequently until the problem finish. Then they back to they regular configuration.