implement minimap blindfold

fixes functionality intended in earlier commit 1176119024fb2352f4c6f98d131409dbd3ed45ab
apply a blindfold during skip replays

independent of the "enter blindfolded" setting, we apply a
blindfold during the skip replays turn, hopefully to speed up
the loading. this will be tested for release in 1.13
Merge pull request #113 from cbeck88/blindfold_minimap

Blindfold minimap