Major Update- New Prologue/tutorial and HUD

This is not THE big one, but nevertheless a big one. The big new features here:

- Prologue. Accessible from the main menu when you start a new game, you can now play through the short prologue to get a feel for various gameplay elements before being prompted to create your party. This should be extremely helpful for newcomers who tend to get stuck on character creation.

- New HUD. Inspired by several requests for more HUD features, the main-game HUD now has two new elements

- the upper menu icon bar. This tells you which keyboard keys take you to which menu sections (oh yeah, that's also new), as well as introduces the "Flee" key, only usable in combat of course.

- the right-hand Buff Bar, which now conveniently shows you which party buffs are currently active. A handy way to realize what you may be missing.

- Also, the ability in the Options menu to change HUD style if you don't like this new one. Either to Buff-Bar only or classic/light. HUD opacity can still be changed in the video options.

Some other minor changes/fixes:

- Added quickload function. F9 (the default key) will now load the most recent quicksave instantly.

- Changed how Prepare Weapons/Armor works: Prepare Weapons now comes with a base additional damage bonus on top of the multiplier bonus. As a result use in early levels should see better results before it evens out at higher levels.

- Fixed error with the Prepare Weapons/Armor icons staying on the party buffs page- these buffs are now removed after every combat encounter as explained in the description

-Fixed minor issue with some chests not saving state

-Fixed missing gold cost for Solar Fusion (sorry)

-Fixed recently introduced bug that prevents characters from learning spells from scrolls