Release 2.1.0: more UI updates

Various things that I've been meaning to clean up in the past year. (No changes to the game content.)

• In the journal window, you can now sort items by name or by date (the order you discovered them in the game).
• Added two new color themes: Sepia and Slate.
• Changed the "Reset" menu item to "Reset Completely" (to match the in-game command for completely starting over).
• Changed the "Close Window" menu item to "Close Game" for the main game window. (Except on Mac, sorry. The Mac's menu bar works poorly with this app framework.)
• Fixed a slight size miscalculation in the status window.
• Updated the Electron app framework to 1.4.16.