Change labels and URLs from Jasig to Apereo.

Jasig is now (with Sakai and others) Apereo.  Adjust `NOTICE` template, hyperlinks, labels, and RSS feeds where feasible to reflect.

Also includes trivial edits to the about uPortal text to allude to uMobile and explicitly claim JSR-286 support.

Re-labels the Jasig News RSS feed reader to Apereo News, but does not change the URL away from `jasig.org` because equivalent `apereo.org` URL apparently not yet available.