Must set annotationType before annotationColor

[pevensen]

I discovered that one must set annotationType before annotationColor, as setting the color generates the image.

It seems unusual for a setter to have such side-effects. One should be able to set either in either order. Would it be possible to either regenerate the image on each setter or delay generating the image until it is actually need. This way the setters could be called in either order.

At the very least, please update the documentation to say that one must set type type first.

[nnhubbard]

Yeah, this was written a long time ago and needs an update. If you have time to do a pull request that would be great. If not I will try to get to fixing this soon.