Reenable test_client_json.py
Reenable test_client_json.py

Issue #1449

dcolligan/server,ga4gh/server,dcolligan/server,saupchurch/server,david4096/ga4gh-server,saupchurch/server,saupchurch/server,ga4gh/server,david4096/ga4gh-server,david4096/ga4gh-server,ga4gh/server,dcolligan/server