FUNCTION
  Bulk file renamer using regular expressions. A knowledge of regex patterns
  is required to use this command safely. The /t switch should be used to
  test a bulk rename process to ensure the file name patterns and replacment
  works correctly.
SYNTAX
  nrename [ path ] patternFrom patternTo [ /s /v /t ]
PARAMETERS
  path ............ The path to scan for files to rename, when omitted the
                    scan starts from the current directory.
  patternFrom ..... Regex pattern to match for files to rename. Use ( ) to
                    define groups in the pattern that can be used to construct
                    to new file name.
  patternTo ....... Regex pattern defining the new file name. Include {n}
                    tokens in the pattern to replace them with the 1-based nth
                    group matched in the patternFrom.
 /s ............... Recursively scan for files.
 /v ............... Verbose processing display.
 /t ............... Test mode, no files are renamed.
EXAMPLE
       nrename "^(\d+)\s+([\w ]+)\.(\w+)$" "{2} {1}.{3}" /s /t
  Recursively scans the current directory in test mode for all files beginning
  with digits followed by some blanks, then a simple file name with extension.
  The new name has the digits moved from the front of the name to before the
  extension. So for example, the file '123 My File.txt' would become
  'MyFile 123.txt'.