update changelog for 1.8 release  - user stories included in RDFa enhancements  - bugfixes and other chores
update changelog for 1.8 release
 - user stories included in RDFa enhancements
 - bugfixes and other chores

emory-libraries/findingaids,mprefer/findingaids,emory-libraries/findingaids,mprefer/findingaids