[ARCH] properties

Hallo,

as part of my effort to check mmi-arch I have used the xml schema to
validate the
the examples. In some cases the examples where not valid against the xsd.
So I went to the text to find out which (xsd or example) was correct.
Unfortunately
the text sometimes lacks this information.

For example "6.2.1.1 NewContextRequest Properties" lists (among others)
Target and Data
as possible Properties. Whereas Data explicitly is defined optional (in
6.1.7) it's not clear from
the text if Target is optional or mandatory (in 6.1.3). Only it is said that
the value must be
an address. The same goes for the Immediate property.

Other specs often use tables to outline child elements and attributes. I
would recommend using a table, too.
One column of the table could define if a property is mandatory or optional.
Also by using joint cells
mutually exclusive properties could be outlined well.

Regards,
Jakob.