Use of preprocessing database to process simulated data

[adrien-laposta]

This PR includes new functions to process a simulation following the data processing (using PR #873) :

• New function site_pipeline/preprocess_tod.load_preprocess_tod_sim that allows to load a CAR map into tods
• Changes of the Pipeline.run() method allowing to skip some steps in the pre-processing configuration file with a boolean flag skip_on_sim
• New function to derive the median across detectors of the noise fit parameters to allow for non-fixed parameters in the pre-processing configuration file in the fourier_filter steps. e.g. :

  - name: "fourier_filter"
    signal_name: "demodU"
    wrap_name: "demodU"
    process:
      filt_function: "counter_1_over_f"
      trim_samps: 2000
      noise_fit_params: True
      noise_fit_array: "noiseQ_fit"
      filter_params:
        fk: "fknee"
        n: "alpha"

[adrien-laposta]

I indeed tested it for the other filters (i.e. sine2 and butterworth filter). Thanks for your comments, I will add filtering scripts using this feature on pwg_scripts soon.