Sen2cor has unstated dependencies

Sen2cor has several unlisted dependencies that are not checked for as part of installation. By attempting to run L2A_Process in a clean conda environment, and installing the modules reported missing, I found pytables, lxml, scipy and scikit-image, psutil, but there may be more that an actual dependency analysis would find.

Most of these packages are all included in a full Anaconda installation, but leaving them unlisted in an environment.yml is very bad practise. Any users installing Sen2cor in an isolated environment, whether a conda env, a clean VM/container, or just a python installation without Anaconda, would have to find the missing dependencies by trial-and-error, as I did, which doesn’t make for a great user experience.