InCommon metadata support

["Cantor, Scott" <>]

> Just to be clear, we're not asking you to remove any of your entities
> from InCommon metadata. Some orgs publish their enterprise SP metadata
> and some don't. It's completely up to you.

Perhaps, but I don't think it works well or provides a lot of value. I used 
to point the non-federated systems on campus to InCommon and eventually I 
realized that wasn't a great idea. For one thing, making changes on campus 
(say, rolling out SLO endpoints in metadata or converting to SAML 2 from SAML 
1) can be coordinated very differently than dealing with all your off-campus 
SPs. Having separate metadata is fairly useful as a buffer between those 
cases, to say nothing of the obvious performance advantages now.

MDQ fixes the latter but doesn't provide the insulation to make local changes 
ahead of global ones.

-- Scott