Show more interesting information about solutions.

* User-defined hints are highlighted based on their contribution to the first-found solution.
* Console messages will be logged if a level loses solutions, gains solutions, or if old solutions are lengthened or shortened due to level changes.
* Several small bugs were fixed.
* Editor will reset Analyzer when a new file is loaded from the pulldown. This is not a complete solution for resetting the analyzer, but it's better than nothing.
* Next step is to find more than just one solution in the solver; hopefully, the analyzer code can remain mostly unchanged.