WIP: Add initial developers page

[nicksellen]

Ok, added a developers page, a few points/questions:

• not sure how it relates to the individual project pages now...
  • we could could consider making the individual project pages not-dev focused at all, and put all the code/repo information on the one /developers page
  • or remove some stuff from the /developers page and put it into each project, not sure which is clearer
• I did not do anything about the content on the wiki for fstool
• I did not write anything about expectations (that was actually my main goal... need to think about it a bit more)

[tiltec]

Not a huge issue, but there is a slight overlap with this blog post of mine: https://blog.foodsaving.world/2017/08/13/ein-paar-antworten.html
(@djahnie is going to translate it into English)

[nicksellen]

Maybe repeating ourselves over and over is useful. People get very confused with the projects I think.

[djahnie]

I like it! And I also think that some redundancy doesn't hurt. It maybe really is useful in this case...