pull latest version of JSON-Schema-Test-Suite
make test errors show the full path to the corresponding JSON test def
resolve nested $refs that point to other $refs

fixes tests/JSON-Schema-Test-Suite/tests/draft4/ref.json|nested refs
blacklist the draft3 remote $ref test (we do pass the equivalent draft4 test)
return a useful error message if max $ref resolution depth exceeded
unit test for extremely deep and circular-$refs
update version to 0.1.1