Add computer analysis mode

[sjamesr]

We should allow the user to analyze games (except for their in-progress games, of course). The user should be able to specify an engine path and we should use that engine to do the evaluation.

[lanternbugs]

I did Lantern Chess in Java starting 12 years ago and made it GPL. It was my "out of college code", and not as styled or designed, but it works. You can use my Running Engine java class if you want in jin analysis as it's license is compatible. https://sourceforge.net/p/lanternicc/code/ci/master/tree/lantern/runningengine.java. It evolved over years I ported it to my Android OpeningTree app and it got improved quite a bit in 2019. it runs on another thread, it opens the engine at the path, it checks for updates on a concurrentlyLinkedQueue(which can also be an update of a move or quit etc) and it prints out output in writeout(). It might have a couple of dependencies like settings. With openingtree i just stubbed a mini settings class at first.