Check for qc_check_complete.json file, and QC status "PASS" before symlinking

[dfornika]

We currently go ahead with symlinking a run if there is an upload_complete.json file in the run dir.

We've put in place a run-level QC checking system that writes a qc_check_complete.json file. That file includes information on the overall pass/fail status of the run. We'd like to only proceed with symlinking if the QC status is PASS.

We should also support other status codes like PASSED_MANUAL_REVIEW, for cases where the initial QC check was FAIL but we decided to allow analysis after manually reviewing the run.