moving the check for the "live" flag into the runProcess function, so will be picked up when not running directly from the command line

This is required for the standard epi model output, which has units of
ha_infected per ha_cell, because the model risk thresholds are fitted
for units of ha_infected per ha_wheat.

Optional config argument to delete mid-process files at the end of a
successful job. There is an associated command-line flag '--clearup'.

The reason for this feature is to provide a way to slim down data
volumes of production runs. A lot of processing files are generated
and production runs may only need to retain configuration, logs and
outputs. Also, the inputs might be archived separately, so they
wouldn't need to be retained in prod runs.

Currently, files are moved to a hard-coded 'recycling bin' directory,
and there is a minimal set of files set for clearup: only the deposition
and environment tar files.

This change requires some standard structure to outputs of
processor_in_job functions, which would be more robust if
a class structure is implemented.

TODO: Implement a test for file clearup.

chore: Tidy imports

And reports are sorted by date.
And assumed disease prevalence is set to medium, not low.

Can be called with command line flag '-p Scraper'.
To use, the config file requires the following minimal entry (with
URL for South Asia):
    "Scraper" : {
	    "ProcessPreJob" : "do_nothing_return_true",
        "ProcessInJob" : "process_in_job_media_scraper",
        "ProcessEWSPlotting" : "do_nothing",
        "seasonStartString" : "20220101",
        "URL" : "https://arrcc-viewer.onrender.com/assets/sample_data/data.zip"
    },