adding 'more' command; raising version to beta2

For implementing irb-like console in the IDE we need to know if current expression (multiline expression) is finished or we should await for more input. 'more' command was added, which does not use the debugger, but uses the exact ruby version (lang-level) used on the debugger side for parsing expressions.
Could you please show the full stack trace to see why lexer needs this method?