Support zero-length tokens in the lexer (fixes #688)
Support zero-length empty lexer rules with lexer commands (fixes #687)
token types bumped by 1 I assume due to recent lexer updates for 0-length tokens or for channel thing?
Merge pull request #696 from parrt/update-unit-tests-token-positions

token types bumped by 1 I assume due to recent lexer updates for 0-lengt...
Merge pull request #691 from sharwell/fix-688

Improved support for zero-length lexer tokens