Patch of demo D-16: new mode signs, starting level 1 by default — icosi-do Steam update #103892

Another tiny patch before Steam's Next Fest. As I'm thinking about achievements (and leaderboards) for the release, I decided to change the signs following level numbers (in SOLO and COOP games), which indicate the current "mode". In practice, the important thing to remember is that you are no longer in a regular game when a "-" is following level numbers. The details are a bit more complicated: If a new game has been started on a level greater than 1, or MOVE LIMIT is off and COLORS are on (or they have been at any time during the current game), then level numbers are followed by "-". This is the easiest mode, which is good for unlocking levels and for trying out individual puzzles. If a new game has been started on level 1 and MOVE LIMIT is on and COLORS are on, then level numbers are followed by "+". This is the usual mode to play "regular" SOLO or COOP games. If a new game has been s...