Temperature flood prevention causing null pointer errors occasionally

[pvince]

The exact error is that there is a null pointer error in, "https://github.com/Hive13/jIRCBot/blob/master/src/org/hive13/jircbot/support/WUndergroundAPI.java" inside the "checkFloodStatus()" function.

I think the issue is as follows:

1. User checks temperature on Day 1.
2. 24+ hours later User2 checks temperature.
3. Sees > 0 events in the log, so no auto-safe, then it removes all items from the list.
4. I think the problem is when it tries to get an iterator over the empty list, it might be returning a null iterator.