Fix xml escaping bug and several improvements

[doino-gretchenliev]

• Fix XML escaping bug. Titles, containing <, >, ", ', & should be escaped, otherwise, they break the XML files.
• Added support for recursive directory processing. Drag and drop a directory, containing multiple game directories.
• Added support for GameCube batch processing.
• Added support for pre-generated icons and banners. Icons and banners could be generated with this script or login could be incorporated into the app later on.

[timefox]

Thank you for helping improve it.