When a division is computed, it must be ensured that the denominator is non-zero to prevent failure of the function call.
Instances include:
((threeMonthLock - threeMonthVested) / THREEMONTHPENALTY)
((sixMonthLock - sixMonthVested) / SIXMONTHPENALTY)
((twelveMonthLock - twelveMonthVested) / TWELVEMONTHPENALTY)
All these storage variables in the denominators are set by the owner in updatePenalties(), and can be 0 as there is no non-zero check.
Before doing these computations, add a non-zero check to these variables. Or alternatively, add a non-zero check in
updatePenalties().
