Parses a single line of a CSV file. Double quotes are allowed arround fields, but they MUST be the first and last character. Escaped quotes are not possible, so there is no way to have a quote as part of a field's value.
Each match includes a possible comma and quotes. To get the field's actual value, look in group #2.
|a,b,c ,"d,e", f||match|
This could use some work to support embedded quotes in the field values.