added git, because npm needs it

oopsie...

ready for review @Magnetme/developers 
Probably it does not depend on it, so it is not included. However it means `npm install` cannot fetch from git repositories. Since our dependencies do not have http or svn fallbacks the installation fails.

So technically apt is correct, but for the use of actually working we need to include it

_apart from that I'm a big fan of always installing things as `git curl wget zip unzip` since you might need it for debugging. None does start a process and their footprint is small_