Mark everything that is not found in the XForms 1.0 spec in a consistent way

Some additions to the XForms 1.0 spec are in the `jr` namespace, others in `orx` and yet others not namespaced at all. We should come up with a convention (color, italics, *...) to mark everything that is an addition to XForms 1.0.

Review the XForms 1.0 specification and inspect the existing additions in the jr and orx namespaces, along with unnamespaced additions. The work is done when the project agrees on a convention for identifying non-XForms 1.0 material and applies it consistently throughout the specification.

Written by the indexing model from the issue text.