Create conda environment using .yml file and not using conda_install and pip_install

[JohannesWiesner]

Instead of using conda_install and pip_install flags use yaml_file (https://www.repronim.org/neurodocker/user_guide/cli.html#neurodocker-generate-docker) and specify local .yml file with all the packages that the CSP-group needs

[JohannesWiesner]

The .yml file should be available in this repository or be included in a submodule that contains a .csv file with all the CSP-packages and a script to parse .csv file into .yml file

[JohannesWiesner]

The repository including an environment.yml file is now available:

https://github.com/JohannesWiesner/csp_conda

It would probably be a good idea to include this as a submodule to have always the latest version of this repo available in this repository