Moved sponsors to yaml file.
Added new speakers pictures.
Update speakers.yaml

+Aleksander Piotrowski
Update speakers.yaml

+Bartosz Gałek,Marcin Wróblewski
Added .dockerignore.
Added meteor development draft project.
Update speakers.yaml

+Paweł Sołtysek
Update speakers.yaml

+Mariusz Sieraczkiewicz
Remove old backend
Simplify run script
Add ruby-dev to build project