Move "Installation instructions" and "Testing installation" to website

• [ ] Create sphinx_presentation/prerequisites.rst
• [ ] Move the related content from README.md into prerequisites.rst file
  • Make sure to convert to use restructure text convention by looking at other *.rst file in the sphinx_presentation folder
  • Make sure to prevent the content added to prerequisites.rst from being included in the presentation slides.

Slides and website can be generated reading these instructions: sphinx_presentation/README.rst