Protect against simple typographical errors

Prior to this change 'ISO-8859-1 ' will present you with an error.
Remove invalid code points, convert everything else

The package presents an error when it detects the encoding as 'CP1252' as well as Windows-1252.  This change allows the package to finish executing without an error and display the text properly.
Merge pull request #7 from blinkums/master

Protect against simple typographical errors