Add Git import capabilities to Docker image

Dependencies

• [2] W3AVITLU First changes for Future Tech
• [3] DETDFBZF Dockerfile voor pijul

Change contents

• replacement in docker/Dockerfile at line 6
  [2.19]→[3.167:215](∅→∅),[3.167]→[3.167:215](∅→∅)
  − RUN cargo install pijul --version "~1.0.0-beta"
  [2.19]

  [3.215]
  + RUN cargo install pijul --version "~1.0.0-beta" --features git