## Summary
These only need the token stream, and we always prefer token-based to
physical line-based rules.
There are a few other changes snuck in here:
- Renaming the rule files to match the diagnostic names (likely an
error).
- The "leading whitespace before shebang" rule now works regardless of
where the comment occurs (i.e., if the shebang is on the second line,
and the first line is blank, we flag and remove that leading
whitespace).
## Summary
This crate now contains utilities for dealing with trivia more broadly:
whitespace, newlines, "simple" trivia lexing, etc. So renaming it to
reflect its increased responsibilities.
To avoid conflicts, I've also renamed `Token` and `TokenKind` to
`SimpleToken` and `SimpleTokenKind`.
