CalCat proxy server to help make detector corrections reproducible

Detector corrections have to query CalCat to find calibration constants. This might be an issue for reproducibility, if CalCat's APIs change, or if it selects different constants to correct the same data. CalParrot stores CalCat responses in an SQLite database for each correction, and replays them if the same queries are made again, so reproducing a correction doesn't need to talk to CalCat again.

This only affects code that works by querying the CalCat REST API, using the settings from cal_tools.restful_config. Code that queries over ZeroMQ, using iCalibrationDB and calDBRemote, will bypass CalParrot.