Better editing for talk node keys
* The fields start out empty, and it is *allowed* to keep *one of them* empty. (A node only needs one key to be useful, right?
* When the node is saved, empty strings are replaced with `" "`. If this is not harmless to the game logic, then I'll need to make the game aware that either key might be `" "`.
* You cannot type more than 4 characters in these fields (unless there's a way to insert characters I'm not aware of).
* If you put 'buy' in a field, it automatically becomes 'purc'.
* There is a note next to the response keys (kind of squished in the corner) enumerating the special logic of the in-game Buy and Sell buttons.
I don't know what it was, but I don't think we could enforce
one even if we wanted to. And it was probably to protect
Spiderweb's IP in the game, which is now Free, so there's
not much point.
Scenedit Quality of life: be helpful when scrolling past boundaries
I've implemented 2 features here:
* When scrolling past the boundaries of the current outdoor section, you will get a yes/no prompt which can load the adjacent section for you at the corresponding center position.
* When scrolling past the boundaries (literal, not the changeable rectangle) of the current town, the editor will ask if you want to jump to the town's entrance in the outdoors. If there are more than one, you can choose.
I did this because I need to be able to find town entrances in the built-in scenarios so I can debug things.
Fixing text buffer texture/font corruption (#479)
* #479 demonstrates that the contents of the text buffer are NOT irrelevant for reproducing bugs. So I set up recording/replay for the burma shave easter egg. This also makes an easy way to mess with the buffer state when debugging (just mash &/\*/&/\*/&/\* n times)
* When a replay throws an error, it puts up a showError() dialog. If the next action is a control_click, the system will try to click that control on the error dialog--which is totally divergent from the replay's intended behavior. So we should just stop replaying when an error happens.
* If you have a long replay and want to run it very fast, but then slow down when you get to the sequence that reproduces your bug, now you can add a `<change_fps>` to your replay to achieve that.
* Fixes for the 2 legacy replay errors that I opened recently
Fix#479Fix#532Fix#533
* Changed shop purchase sound effects where Yum! definitely didn't fit. For alchemy, mage spells, and priest spells, I made the sound the same as the sound when you perform those actions. I figure this actually makes sense because the teacher would show you how to do the thing.
* For skill training, I made the sound be the same as leveling up. I think this makes sense.
* When something is too heavy to pick up, the "Argh!" labeled as 'Action Failure' in the editor sound picker makes a lot of sense--you tried to pick it up and were frustrated.
* I changed beep() so every platform just plays sound effect 1, the one labeled "low beep" [here](http://openboe.com/docs/editor/appendix/Sounds.html) that's labeled "Cancel target lock" in the editor picker. I think this reasonable.
* Removed `ding()` which was an unused alias for `beep()`
