Refactor AlignHash.

Introduce some inner help classes.
Refactor ParenthesesAsGroupedExpression#on_send.

Extract private method spaces_before_left_parenthesis.
Refactor BlockAlignment.

Extract a private method.
Refactor MRISyntaxChecker.offences_for_source.
Refactor CLI by extracting method process_files.
Merge pull request #587 from jonas054/refactor_long_methods

Refactor long methods