SAS7BDAT.convert_file returns True even if interrupted by IOError exception

[John Copella]

The SAS7BDAT.convert_file method will return True even in situations where a file is incompletely converted (i.e., the loop to write data rows is interrupted by an IOError exception), leaving the caller of the API with no reliable way to determine if the SAS dataset has been fully exported to the CSV file.

[Jared Hobbs]

fix #45:

set the success flag to False on exceptions

→ <<cset 4a7fa5e9ef61>>