Add option for justifying columns with whitespace before field (after comma)

[tyhenry]

i.e.

John Doe    ,1  ,manager
John Doherty,200,employee

becomes

    John Doe,  1, manager
John Doherty,200,employee

This would help when parsing CSV files with Python's csv reader, which can ignore initial whitespace in a field, but not trailing whitespace (AFAIK):

https://docs.python.org/3/library/csv.html#csv.Dialect.skipinitialspace