More fixes for map-specific crashes, fixes #1427 and #733
- if special victory condition is present AND there is only one player
normal victory condition will be disabled
- added new triggered condition, constant value
- if target of CONTROL/DESTROY condition is removed from map, triggered
condition will be replaced with constant
- fixed randomization of armies with random stacks


git-svn-id: http://svn.code.sf.net/p/vcmi/code/trunk/@3747 4dfc6b2a-8b31-0410-aa91-d6c70e3ac834