Documentation: Consolidate Technical Documentation #360

Quincy suggested all technical docs go into CONTRIBUTING.md on the Jan 25 2020 meeting.

• 1. Move https://github.com/freeCodeCamp/chapter/tree/master/server/docs to CONTRIBUTING.md
• 2. (edited) Move https://github.com/freeCodeCamp/chapter/blob/master/docs/how-to-open-a-pull-request.md into an collapsed / expandable section within Step 4 of the CONTRIBUTING.md
• 3. We can delete /docs/ directories, except /images since it's only general stubbed out stuff from really early on.
• 4. Is there a better place to store CONTRIBUTING.md screenshots than in /docs/images? If not, then do we want to rename it.
• 5. As with the "Step 4" note above, we can / should use expandable sections in CONTRIBUTING.md to make certain sections not take up as much space until someone clicks to expand.
• 6. @Narutuffy was looking to get involved and I thought it could be an easy first contribution
• 7. Improvements to CONTRIBUTING.md on the technical side. - Closed via Update DOCS #396 and Improve Node, Docker, Postegres and Other Sections of CONTRIBUTING.md #447
• 8. This also begs the question of if some of the README.md technical documentation is better in CONTRIBUTING.md. These sections of the README may be better in CONTRIBUTING.md: Schema, API Specs, Testing - Closed via Move server/docs/README.md into CONTRIBUTING.md, per Quincy #397