switched to a single field method for adding a checksum, string like alg
removed title and version properties from extension schema object
adds format:uri to badgeclass where needed
deletes errant comma making json invalid
adds regex pattern for checksum to match, w/ escaped backslashes
corrects regex pattern for checksum to match, w/ escaped backslashes
including recent updates to schema, including checksums.
added a couple format:uri, deleted title/version in assertion