Inform user of default avatar selection

[toonarmycaptain]

When prompted to select avatar, user sees dialogue box titled 'Select .png format avatar:'

• no indication of option to use default avatar by clicking cancel, or that default avatar will be used if none is provided by user.
• No feedback of "no avatar provided, default avatar will be used", or "xyz.png" selected when avatar is provided or not.

Some feedback on as student data is entered would be ideal. eg:

Enter student name, or 'end', and hit enter: 
Tom - toms_avatar.png
Dick - No avatar provided, default avatar will be used.
Harry - harry.png

# Inform of ability to change in edit menu when this feature becomes available.

[toonarmycaptain]

GitMate.io thinks possibly related issues are #98 (Option to set default avatar by class. ), #69 (Use default avatar in place of bad avatar), #99 (User enters malicious data), #33 (Take avatar images and process them), and #67 (Make avatar images save in correct folder. ).