Fixes crash when trying to print spanish accented characters.

[Goles]

    Traceback (most recent call last):
      File "./exitwp.py", line 353, in <module>
        data = parse_wp_xml(wpe)
      File "./exitwp.py", line 164, in parse_wp_xml
        'items': parse_items(),
      File "./exitwp.py", line 127, in parse_items
        body = gi('content:encoded')
      File "./exitwp.py", line 120, in gi
        print result

    UnicodeEncodeError: 'ascii' codec can't encode character u'\xe1' in position 236: ordinal not in range(128)

Now is will display an encoding error on the writing of the files (not resulting on a crash anymore).

writing............................................................................................
 Parse error on: Blog post title where the error happens
.................................

This fix could still be improved to fix the writing but don't really have the time right now.

[thomasf]

thanks