fix #47
Only mark unknown schemas as unresolved. This stops previously loaded schemas from being nulled when referenced, it also makes sure that $refs only are pushed to unresolvedRefs once.
Adding tests to check that
- previously added schemas not are nulled when referenced by a second schema
- $refs not are pushed to unresolvedRefs if the schema has been added
- schemas can reference and use previously added schemas
Do not consider default value when validating enum
Merge branch 'master' of https://github.com/jkryl/jsonschema
Merge branch 'master' of https://github.com/hugowetterberg/jsonschema
Add more support for v4 features and upgrade to latest test suite