Fix NDC $lookup, add code system properties and filter and $translate between 10 and 11 digit codes.

[rhausam]

Add 'code-type' and 'synonym' properties to code system and return in $lookup. Add 'code-type' filter to code system to allow value set definitions for "10-digit-only" and "11-digit-only" (etc.) value sets. Create (implicit) concept map to declare equivalence and support translation between 10 and 11 digit codes for an NDC concept.

NDC_10_&11_digit_examples.zip

See related Zulip topic.