69: Incremental reparsing for single tokens r=matklad a=darksv
Implement incremental reparsing for `WHITESPACE`, `COMMENT`, `DOC_COMMENT`, `IDENT`, `STRING` and `RAW_STRING`. This allows to avoid reparsing whole blocks when a change was made only within these tokens.
Co-authored-by: darksv <darek969-12@o2.pl>