add Documentation target
add drawing of annotations to RadarView
documentation updates
appledoc seems to be not able to handle a newline after param name and description
change findArvosObject:
fix: this would give object address, not its value
simplify logic for loadGlTexture and have a textureLoaded readonly property in ArvosSquare
code cleanup and fail on wrong initializer
return error with description
remove handling of unreachable code
remove unused ivar