Fixed level editor mouse stuff.  Had to change mouse_state to avoid sliding caused by precision loss when going back and forth between SDL events and the mouse_state with USE_CONTROLLER_INPUT.
Bumped version number to 1.1.0.
Decreased Yo delay.
Added LevelData::dead_list to delay deletion of walkers until we don't need them anymore.  In particular, some weapons could have an invalid owner pointer if we freed a dead walker.  Now there's still a problem with the list node deletion that happens in remove_ob(), when already iterating that list.
Big, scary changeset...  Refactored lists from oblinks to STL lists.
Removed oblink stuff for good.
Merge branch 'master' into dinomage