Log Message:
Update to 20180220

Upstream changes:
2018 02 20
      - RT #124469, #124494, perltidy often making empty files.  The previous had
        an index error causing it to fail, particularly in version 5.18 of Perl.

        Please avoid version 20180219.

  2018 02 19
      - RT #79947, cuddled-else generalization. A new flag -cb provides
        'cuddled-else' type formatting for an arbitrary type of block chain. The
        default is try-catch-finally, but this can be modified with the
        parameter -cbl.

      - Fixed RT #124298: add space after ! operator without breaking !! secret
        operator

      - RT #123749: numerous minor improvements to the -wn flag were made.

      - Fixed a problem with convergence tests in which iterations were stopping
        prematurely.

      - Here doc targets for <<~ type here-docs may now have leading \ 
whitespace.

      - Fixed RT #124354. The '-indent-only' flag was not working correctly in the
        previous release. A bug in version 20180101 caused extra blank lines
        to be output.

      - Issue RT #124114. Some improvements were made in vertical alignment
        involving 'fat commas'.