Fixed Integer overflow for TerraShatterer

[DefaultEugene]

Hi there!
I found an issue with the TerraShatterer. Since its mana cap is Integer.MAX_VALUE, it is the only item vulnerable to the Integer Overflow problem

If the pickaxe has (MAX_MANA - 5) mana and we try to add 10 mana, the mana value will wrap around and reset to 0. I've fixed it using a safe comparison before adding

I also want to draw attention to the getMana method: it returns stack mana * stack count, which can also cause an overflow. However, that bug is not as critical as this one (since it requires a stack size > 1 for an unstackable item) and would require a much more complex fix using long arithmetics

[TheRealWormbo]

Did you actually find an overflow scenario? The only way mana is added to the Terra Shatterer is via a mana pool, and that should be limiting the amount of mana to exactly reach the maximum.

[edit] (Though I agree the limitation implemented in addMana is ineffective.)