Added hit/damage detection using packets.

Added hit/damage detection using packets to defensive spells.

Player will now only use a defensive spell if their hp is <= to the slider value and  damage.
Not sure if you wanted it for every defensive item but we could talk about it on irc. :p
Update MActivator.cs

Fixed a little error there.
Merge pull request #3 from Kurisu44/master

Added hit/damage detection using packets.