Simple Dockerfiles for both CPU and GPU

[tomasiser]

Description

The official Mitsuba 2 repository does not contain any Dockerfiles to be easily able to run Mitsuba 2 in a container. Because not everyone wants to run software on bare machines, and also to simplify reproducibility, @diiigle and I made two very simple Dockerfiles based on Ubuntu that support both CPU and GPU variants.

The images also directly support Python 3 and Jupyter to be able to easily run experiments.

The pull request contains two Dockerfiles and a separate README file.

Please let me know if this pull request is acceptable and/or if some changes to the original documentation should also be made. :)

Testing

No automated testing available

Checklist:

Please make sure to complete this checklist before requesting a review.

• My code follows the style guidelines of this project
• My changes generate no new warnings
• My code also compiles for gpu_* and packet_* variants. If you can't test this, please leave below
• I have commented my code
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I cleaned the commit history and removed any "Merge" commits
• I give permission that the Mitsuba 2 project may redistribute my contributions under the terms of its license