Merge pull request #590 from Ragora/bugfix-projectile-on-add

* BugFix: Correct the onAdd callback not being raised for Projectiles

Engine/source/T3D/projectile.cpp

@@ -786,6 +786,8 @@ bool Projectile::onAdd()
       // If we're on the server, we need to inherit some of our parent's velocity
       //
       mCurrTick = 0;
+
+      scriptOnAdd();
    }
    else
    {