Fix build (#289)
Fix build (#289)

Having the `no_avatar.png` image listed in the `.csproj` `<Content Update="">` seems to have broken the build on OS X and Linux. This modification should fix that.
haraldnagel/gra4,haraldnagel/greatreadingadventure,MCLD/greatreadingadventure,MCLD/greatreadingadventure,justinmeiners/gra4,MCLD/greatreadingadventure,haraldnagel/greatreadingadventure,iafb/gra4,haraldnagel/greatreadingadventure,MCLD/gra4,iafb/gra4,MCLD/greatreadingadventure,haraldnagel/gra4,justinmeiners/gra4,haraldnagel/greatreadingadventure,MCLD/gra4,MCLD/greatreadingadventure