assessment workflow

[david-beauchesne]

For now, I built the package so that it is pretty straightforward and only does what is necessary for the cumulative effects assessment. It may however be interesting to provide a way to provide a configuration yaml to an assessment function that provides all the necessary informations to perform the assessment, and perhaps even a link with the pipedat package to allows a user to format the data necessary for the assessment on top of actually running the analyses.