update documentation for group attribute edit

I tried following the demo at https://spaces.at.internet2.edu/display/Grouper/Grouper+attribute+framework+attributes+editable+in+group+edit+screen and I couldn’t get it to work. I found that the keys in the example grouper.properties are not what the code is expecting. The example has these:
groupScreenType.theConfigId.attributeName
groupScreenType.theConfigId.label
groupScreenType.theConfigId.description
groupScreenType.theConfigId.index
What I found in the code, and which work for me, are these:
groupScreen.attribute.theConfigId.attributeName
groupScreen.attribute.theConfigId.label
groupScreen.attribute.theConfigId.description
groupScreen.attribute.theConfigId.index
Also, grouper.base.properties has the same issue.