Elves able to clear jungle without sanitation

[bc1]

I meant burning *jungles* to transform them into forest.
Burning forests to speed up improvement building would not work well for the elves because of the time it takes for spreading fires to burn out on its own (keep in mind a bug makes forests disappear if the spring spell is used). However it is useful for the other races to build improvements in forests, but that's another bug exploit.