Externalize annotation display macros in spearate pages each for easier customization.

Currently, all the main macros that handle the display of an annotation are packed into one AnnotationCode.Macros page.

If someone wants to customize something in the way annotations are displayed, he needs to customize that page.
If someone wants to package those customizations into an application, he would have to package the entire page with all the other macros as well, needing to maintain all the macros.

An idea would be to externalize each of these macros into separate XWiki pages so that each customization (toolbox, annotation body, etc.) can be easily included in applications.

If not, at leas the annotation body display macro should be externalized, since that is probably the most customizable one.