#115 debug tab refreshes a lot of times when visualizing even a few variables

[Isaac]

when debuggign some code and visualizing some pointer variables in the watch every time i press "next line" the debug tab refresh a lot of times, so it takes a long time to go next instruction.

[orwelldevcpp]

The debug variable tree now refreshes only once per step through the code instead of once per updated variable (per step).