[FEAT] Window caption now displays level info, etc.

[WillLem]

Now that we have a way to display singular and plural custom names, it's a better time than ever to have level info display on the Window caption (aka Title bar):



Here's an example of singular form:



And, custom lemming names (in this case, Lemminas):



In light of this change, I feel it's now no longer necessary to display the "rescued" count as a negative number in the panel. Instead, the number is displayed in red until the save requirement has been met:





In addition to this, the caption reads "Mass Replay Check" when a MRC is being performed.