[instrument_manager] Use JSON data for uploaded linst instruments

[driusan]

This updates the instrument_manager to create a .meta file for uploaded LINST instruments to use JSON for saving data, rather than running the generate_tables_and_test_names script. This is more robust, doesn't require exec'ing mysql, doesn't require create table permission for the upload, and better aligns with LORIS best practices to use JSON instead of table data by default.