added LiveSource to ESP
fixed bug with augmentation IDs.
Merge branch 'master' of https://github.com/Firebusa/ARdevKit.git
Merge branch 'WorkBareus'
implemented change event for propertyGrid, in which the user cannot set an path (image, picture, option, whatever) to null.

added some comments and cleaned the code a little bit
implemented the things in issue  #94 . i have changed it in this way, that, if someone sets a path (data, image, option path) to null, it will restore the value.