Organization of experiment

The davai-new_xp command-line prepares a "testing experiment" directory, named uniquely after an incremental number, the platform and the user.

This testing experiment will consist in:

conf/davai_nrv.ini : config file, containing parameters such as the git reference to test, davai options, historisations of input resources to use, tunings of tests (e.g. the input obs files to take into account) and profiles of jobs
conf/<USECASE>.yaml : contains an ordered and categorised list of jobs to be ran in the requested usecase.
conf/sources.yaml : information about the sources to be tested, in terms of Git or bundle
venv/ : python venv to be used by the experiment. Either a link to an existing venv, or an actual virtualenv in editable mode
a logs directory/link will appear after the first execution, containing log files of each job.
DAVAI : in case of editable mode, a clone of the DAVAI repository, checkedout on the requested version, used by the venv
links to the python packages that are used by the scripts and not pip-packaged yet (only vortex remains at present)