More tolerant to user data which cannot be processed

[FlorinTulba]

Description: The application was requested to load a font family not encountered before that:

• did appear within the Font Dialog
• could not be located within Windows registry in HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Fonts. Pic2Sym takes the path of the font family from such an entry in the registry. It threw runtime_error with the message "FontFinder::extractResult : Couldn't find this font within registry!"

This type of problem should not break the application. Instead, the user needs to receive a short explanation why the provided data could not be processed and the application could just invite the user to select a different piece of data.

[FlorinTulba]

Solved by commit e5021a4664babf642ff615f8e6aee316ea6cc314 in v2.0 .