Updated comment of example 'walk'
Corrected comments
Changed library 'keyboard' to return always the ascii code of the upper case (like in webots).
Added comment
Merge pull request #121 from DavidMansolino/WalkComment

Updated comment of example 'walk'
Merge pull request #122 from DavidMansolino/KeyboardImprove

Changed library 'keyboard'
Set keyboard window as not resizable.
Added explanation text in the keyboard window.
Corrected small forgetting.
Added comment.
Added possibility to add an image, and debug text show.
Merge pull request #123 from DavidMansolino/ImproveWindow

Improved keyboard window