Document options for sqlformat --comma_first

[jidanni]

Please say exactly what the choices for COMMA_FIRST are.

$ sqlformat -h
...
  --comma_first COMMA_FIRST
                        Insert linebreak before comma (default False)
$ sqlformat ... --comma_first False file.sql | sum
03925     1
$ sqlformat ... --comma_first True  file.sql | sum
03925     1
$ sqlformat ... --comma_first xxx   file.sql | sum
03925     1
$ sqlformat ... --comma_first 0     file.sql | sum
03925     1
$ sqlformat ... --comma_first       file.sql | sum
03925     1
usage: sqlformat  [OPTIONS] FILE, ...
sqlformat: error: argument --comma_first: expected one argument
00000     0
$ sqlformat ...                     file.sql | sum
05618     1
$ sqlformat --version
0.4.1