Rewritten adding leader to a party.

git-svn-id: http://keeperfx.googlecode.com/svn/trunk@1458 40a56aae-0377-11df-bfb3-7781b9cb07ea
Rewritten some of creature grouping code. Fixed parties following tunnellers.

git-svn-id: http://keeperfx.googlecode.com/svn/trunk@1459 40a56aae-0377-11df-bfb3-7781b9cb07ea
Fixed counting creatures which are joining the dungeon.

git-svn-id: http://keeperfx.googlecode.com/svn/trunk@1460 40a56aae-0377-11df-bfb3-7781b9cb07ea