fixes

[arnetheduck]

• fix end-of-token information in lexer/parser for better empty line retention
• move several postfix comment splitters up the AST for better fidelity with original source
• fix several cases of spurious end-of-list commas when only a single list item was present
• fix several cases of spurious over-indent
• more accurate line length prediction, fixing several cases of spurious line breaks
• command syntax now prefers additional arguments on a new line if it doesn't fit on a single line
• exported fields are considered simple and don't use one-per-line formatting
• fix import/except formatting