[docs/NF] add Alexander Ecker to the list of contributors
[docs/NF] add Alexander Ecker to the list of contributors

esc/Psignifit-3.x,esc/Psignifit-3.x,esc/Psignifit-3.x,esc/Psignifit-3.x,esc/Psignifit-3.x,esc/Psignifit-3.x