Modified spell drawing for possession and casting over battle message to only use spell cursor when spell is available.

git-svn-id: http://keeperfx.googlecode.com/svn/trunk@1429 40a56aae-0377-11df-bfb3-7781b9cb07ea
Removed the old hard-coded function for checking possession target.

git-svn-id: http://keeperfx.googlecode.com/svn/trunk@1430 40a56aae-0377-11df-bfb3-7781b9cb07ea