[TASK] Add balance_change array to transaction response, computed from metadata

This is how I read Brandon's comment:

"Not all of... ripple-* need to be 100% consistent. If you think it's realistic to weed out all the... inconsistencies, ..., I urge you to take a good look. Not only do we not need to enforce consistency..., we haven't been from the beginning. "

If the only benefit to putting a semicolon at the end of every function declaration is to "make them all the same" it's not worth it. Same for underscores versus camel case. A lot of style is subjective; imposing one company-wide standard creates only conflict at best, with no commensurate gain. Apologies in advance for my poor JavaScript understanding, if the presence of the semicolon in question has an affect on the program's behavior.