Note regarding latest distributions

[Cantor, Scott]

Scott Koranda caught that I forgot to update the pkg_config checks in the opensaml and SP configure scripts, they should be checking for >=3.1 of the xmltooling and opensaml dependencies instead of 3.0. That might have to be patched for the Debian packaging, don't know how strict that's all managed. I patched the master branches already.

-- Scott