Fix for #1624 :
- recreate adventure map interface on each scenario (to make sure that
there is no garbage data from prev. game)
- added check to avoid such situations in future


git-svn-id: http://svn.code.sf.net/p/vcmi/code/trunk/@3664 4dfc6b2a-8b31-0410-aa91-d6c70e3ac834