Speed up UnicodeJsps/properties.jsp (properties page)

[macchiati]

The property index has gotten very slow. I'm not sure why, but maybe the move away from using ICU properties on the backend.

The UI has always been a hack; it shows the property values, but hides the long ones. You have to click on
Show Values and it takes a while to open up.

I suspect that this is because the page is rebuilt on the server side with each access. But that is a waste, because the whole page could be static, never hitting the server at all. So one way to speed it up is to just build a static page once.

It would rebuild any time the UnicodeJsps starts up after the code is rebuilt.
It would have a little bit of javascript that would show/hide values, eg with a "twisty".