[xliff] context-type attribute.

Here is why I was confused with whether or not context-type:

The bottom of the Summary column for issue #7 of the last meeting issue
summary
http://lists.oasis-open.org/archives/xliff/200302/msg00001.html
reads:

"Combinations of these values can be made via the standard mechanism of
XLIFF. Thus, purpose="location;match" would provide both location and TM
matching contextual information. The schemas for this are detailed in the
original suggestion URL"

I know I didn't dream this up.

-yves