Add 3 new features when choosing user image profile

[ekickx]

The three new features that I add are:

• Circle crop: Round the selected image;
• Zoom: Can zoom selected image
• Move: Move the selected image with x & y coordinate

This is the screenshot of mugshot with my changes.

This is the first project I am working with PyGobject so maybe my code is messy. And sorry for my bad english :sweat_smile: . Look foward for the review :smile: .