Importing duplicate multi-disc games doesn't differentiate duplicates

[fraganator]

Importing multiple duplicate games (from different regions) which are also multi-disc doesn't detect the individual games. Instead a single game is imported, but the Additional Apps points to discs from both regions.

Steps to reproduce:

• In File Explorer, select the files for a multi-disc, duplicate games (e.g. FF7 (US) and FF7 (Europe)).
• Drag and drop all of the files into LaunchBox and import them, allowing duplicate games

Tested in LB v7.0, Windows 8.1 64-bit