[WIP] Pretty Printer

The only known issue (apart from the slight ugliness of the code due to the nontrivial rules for pretty whitespace) is that the main method is pretty printed as `public void main(String[] args) {...` (dropping the `static`).
Probably not -- there should be a newline after `error`. The finding should be on its own line (also if you redirect `stderr` to `/dev/null`, the command prompt will probably be printed directly after `error`, which is ugly).