Clean pids that match the URL regular expression

In order to filter out both "https://" and "http://", use the URL regular expression in the pid cleaner method for substitution
Set the desired prefix with "let" and use the memoized helper method in the example
In the FacultyDigitalArchive ResourceSet, set the "http" identifier before we create the Nyucore model
Add examples to the FacultyDigitalArchive spec when the record has multiple examples
Refactor the :add_identifier_as_available_or_citation method that is used before we create an Nyucore model for cleanliness and readability
Update the FDA example in the DataLoader spec based on the latest FacultyDigitalArchive code
Update the FacultyDigitalArchive and DataLoader VCR cassettes based on the latest code