Collapse dstr with only str children to a str for CLI
Use simpler implementation of Emitter#delimited
Adjust flay score
Add a preprocessor that normalizes regexp quoting
Correct unparsing of regexp node quoting with options
Allow to pass nil nodes from CLI preprocessor

nil is a valid output of parser. So it must also be a valid input.
Fix termination of op asgn nodes
Add support for return with multiple children
Correctly emit some return edge cases
Simplify return emitter
Cleanup multiline block chain
Cleanup multiline chaining of blocks
Remove defunkt CLI exception handling
Prefer Parser::AST::Node#updated over .new
Cleanup return emitter
Adjust reek config for false positive
Break up big preprocessor method
Adjust flog score
Add UTF-8 encoding comments for 1.9.3
Remove unneded lvar assignment