Moved basic type validation code into its own module
Changed "_validate" to "validate_key", to make things clearer
Forgot to update POD
One too many options in the condition list
Adding a type to cover payload keys whose values are another class
Implemented a function to fill in missing UUIDs and identifiers
Removing array of dictionaries and array of strings

These should be implementable using other types
Update description of the contents of the payload key hash
Revert "Removing array of dictionaries and array of strings"

This reverts commit 7be99760c83ade1ac140274230747ce28196226c.
Remove ArrayOfDicts and ArrayOfStrings types
Remove vestigal array- and dict-validation code
Remove array-dict and array-strings from the list of test files
Update array tie to only take one parameter
Update FETCH with code to create array/hash/class objects on first
access
Uppercase tie methods, and keep validated items in a separate array
Update UUID test to check arrays of UUIDs