Lab 9. Restricting the Content of <appliance>

Copy the schema you created in Lab8 into
this folder.

In Lab8 you made the content of <appliance>
conditional to the value of the kind attribute.

However, kind was declared to be of type string.
Consequently the content of <appliance> was a
stereo type or a juicer type or an appliance type. 
 
We want the content of <appliance> to be only
a stereo type or a juicer type, and nothing 
else. Modify your schema to achieve this. 