Bug#327021: Slight correction of the sample code

[Wolfgang Roemer <wolfgang.roemer@gmx.net>]

Hello,

of course the QRegExp to show the wrong conversion must look like this:

QRegExp unallowedChars (QString ("[a-zA-Z;:,!@#$%^&]"));

Nevertheless you will see the wrong conversion also already in the output of 
the converted string (first output line of sample code): The intial double of 
13.0 will be converted to a QString of "12.:"

WR