* feat(ISSUE-11033): add null encodable type and mustache changes
* feat(ISSUE-11033): regen all swift5 samples
* feat(ISSUE-11033): add swift5 examples of null encodable
* feat(ISSUE-11033): fix hashable and compliation issues
* fix(ISSUE-11033): fix tests by using new enum encodeValue
* fix(ISSUE-11033): fix tests by using new enum encodeValue
* fix(ISSUE-11033): revert status back in pet api test
* fix(ISSUE-11033): fix issue with objc compat generator
* feat(ISSUE-11033): restore default values to null encodables
* chore(ISSUE-11033): rename default value for null encodable
* chore(ISSUE-11033): add test cases with different nullable defaults
* add swift5 option for generating frozen enums
* use case unknownDefault to avoid conflicts
* update comments to reflect unknownDefault case
* set default values for unknown case to avoid conflict
* dont need vendor extensions to detect enum raw data type
* move CaseIterableDefaultsLast into models mustache template
* comment catch all case and add support for other types
* add frozen enums to ci pipeline
* remove extraneous edit to extensions template
* remove left over protocols files
* small comment and case adjustments