Annotations and (small) image enhancement

I fixed/enhanced a few things:

1) I fixed a little bug fix in `doc.text`. It was failing in word wrap mode when called with an empty string.

2) Annotations (underline and url) did not work with word wrap mode. I fixed it by introducing `underlineColor` and `url` options to doc.text.

3) Annotation coordinates were completely off after transforms. I fixed it with an `@matrix` in the document

4) I enhanced `doc.image` so that you can pass image data in case if you don't load the image from a file.

Otherwise, this is really a very neat and helpful package. Thanks for making it available.

Bruno