Scripting things

Made items in containers (including npcs, creatures and the player) with scripts attached to them have the script run, like in vanilla morrowind.
This was mostly a prelude to my original goal, which was implementing these special variables: https://wiki.openmw.org/index.php?title=Scripting_(status)#Set_by_game

So far, I only implemented OnPCEquip, but I'll do the others too.

Oh, and I also added vim swap files to .gitignore, because it was annoying me :P