Add suffix when duplicated image name

[jecisc]

I just updated my Launcher and before I used a really old version. Using this new version I see a regression compared to the previous version.

Imagine I have those images in my launcher:

• Pharo
• Pharo-01
• Pharo-02

If I create a new image of Pharo, in my previous version it proposed me to call it Pharo-03. Now it proposes to call it Pharo and it fails when I accept because I already have an image of the same name.

IMO it would be good to get the old behaviour back.