Rewrittes some of research. Moved relation between a spellbook and keeper power to config files. Added spellbook to be used for possess spell.

git-svn-id: http://keeperfx.googlecode.com/svn/trunk@1435 40a56aae-0377-11df-bfb3-7781b9cb07ea
Implemented a few more creature statistics.

git-svn-id: http://keeperfx.googlecode.com/svn/trunk@1436 40a56aae-0377-11df-bfb3-7781b9cb07ea