Revised document conformance text

[MURATA Makoto (FAMILY Given)]

Chris,

I think that the three subclasses were introduced since some application
programs can handle only one of WML, PML, and SML.

One could argue that we should either go further (such as "WML
strict-horizontal-writing-only-black-and-white-only") or  
stop at "Strict".  How do people feel?

If we really drop the subclasses, we have to be thorough.  Part 4 has 14
occurrences of "ML Transitional" and 3 occurrences of "ML strict", while
Part 1 has 17 occurrences of "ML strict" and 6 occurrences of "ML transitional"


Cheers,
Makoto